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  • How to Import Subscriber Phone Numbers

    This guide walks you through how to import subscriber phone numbers into Sender for the first time, so your contacts are ready for SMS campaigns.

    Where to Find This Feature

    In the Sender dashboard, go to: Subscribers → Subscribers → Add subscribers

    This opens the Import subscribers page, where you can upload a file containing subscriber data including phone numbers. You will see four import methods at the top of the page: Import from a file, Copy/Paste subscriber list, Import from Mailchimp, and Import from GetResponse. Below the import method tabs, you will find a file upload area, a list format example, and template download options.

    Steps to Import Subscriber Phone Numbers

    Step 1 — Prepare Your File

    Before uploading, format your file so that each subscriber is on a separate row and each field (email, first name, last name, phone number) is in a separate column. Phone numbers must be in international format with the country code prefix (e.g., +1 for the United States, +44 for the United Kingdom). For example: +12345678901.

    Sender accepts .csv, .txt, and .xlsx (MS Excel) files up to 64 MB. You can click Download Excel template or Download CSV template on the import page to get a pre-formatted file to work with.

    Step 2 — Upload Your File

    On the Import subscribers page, make sure the Import from a file tab is selected. Drag and drop your file into the upload area, or click the Import file button to select a file from your computer. Sender will process the file and display a preview of your data in the next step.

    Step 3 — Map Columns to Subscriber Fields

    After uploading, Sender displays the Match the columns section with a preview of your data. Each column has a dropdown at the top. Verify that Sender has correctly matched your columns to the right subscriber fields — particularly that your phone number column is mapped to Phone number.

    If a column is not matched correctly, click the dropdown and select the correct field. You can also search for a field by name, select Create a new field if you need a custom field, or choose Skip this column to exclude a column from the import. A count at the bottom shows how many subscribers will be imported.

    Step 4 — Assign to a Group and Start the Import

    Below the column mapping preview, you will see the Add subscribers to a group section. Click the Choose groups dropdown to assign imported subscribers to one or more existing groups, or select Create a new group to make a new one. Assigning subscribers to a group makes it easier to target them later in SMS campaigns.

    When everything looks correct, click the Start import button. Sender processes the import and returns you to the Subscribers list, where you can verify that the new subscribers and their phone numbers appear.

    SMS Compliance Requirements

    Consent (TCPA / GDPR) — Before importing phone numbers, you must have explicit opt-in consent from each subscriber to receive SMS marketing messages. In the United States, the Telephone Consumer Protection Act (TCPA) requires prior express written consent. In the European Union, the General Data Protection Regulation (GDPR) requires a clear legal basis for processing personal data, including phone numbers. Only import phone numbers for contacts who have given you verifiable permission.

    Phone number format — Sender requires phone numbers in international format, which includes the country code prefix followed by the subscriber's number (e.g., +14155551234). Numbers that do not include the country code may not be recognized correctly and will not be usable for SMS sending.

    Opt-out instructions — Most carrier regulations and Sender's own SMS policies require every marketing SMS to include opt-out instructions, such as "Reply STOP to unsubscribe." While this requirement applies when sending messages rather than during import, ensure your imported list only contains subscribers who have not previously opted out.

    Purchased or rented lists — Do not import phone numbers from purchased, rented, or scraped lists. Sending SMS messages to contacts who have not opted in violates carrier policies and SMS regulations, and may result in account suspension.

    Always consult a legal professional for guidance specific to your jurisdiction and business.

    What Happens Next

    After importing, go to Subscribers → Subscribers and click on any imported contact to view their profile. The subscriber profile displays an SMS campaign section showing the imported phone number with its status (e.g., ACTIVE). The Subscriber activity log on the right side of the profile confirms the import with entries such as "Phone set to [number] — Source: Import."

    Imported subscribers with valid phone numbers are immediately available for SMS campaigns. To verify your setup, you can send a test SMS to your own number by creating a new SMS campaign from SMS campaigns → New campaign.

    You can manage subscriber phone numbers, group assignments, and field mappings at any time from the Subscribers section of the dashboard.

    Common Issues

    Phone numbers not appearing after import → The phone number column was not mapped to the Phone number field during the column matching step. Re-import the file and make sure the dropdown above the phone number column is set to Phone number.

    Phone numbers in incorrect format → Numbers missing the country code prefix (e.g., 5551234567 instead of +15551234567) may not be recognized. Update your file so every phone number starts with + followed by the country code, then re-import.

    Subscribers not showing as SMS-active → If a subscriber's profile shows the SMS campaign section but the phone number is missing or the status is not ACTIVE, the phone number may have been formatted incorrectly or the column was skipped during import. Check the subscriber's profile and edit the phone number manually if needed.

    File upload fails → Sender supports .csv, .txt, and .xlsx files up to 64 MB. Make sure your file is in one of these formats and does not exceed the size limit. If the file is too large, split it into smaller batches.

    Duplicate subscribers → If a subscriber with the same email address already exists, Sender updates the existing record with the imported data, including the phone number. This does not create duplicate entries.

    FAQs

    What file formats does Sender accept for importing subscribers?

    Sender accepts .csv, .txt, and MS Excel (.xlsx) files. The maximum file size is 64 MB. You can download a pre-formatted template from the Import subscribers page by clicking Download Excel template or Download CSV template.

    What phone number format does Sender require?

    Phone numbers must be stored in international format with the country code prefix (e.g., +1 for the United States, +44 for the United Kingdom). The full number should start with + followed by the country code and subscriber number, such as +14155551234.

    Do I need consent to import subscriber phone numbers?

    Yes. SMS regulations like TCPA (US) and GDPR (EU) require explicit consent from recipients before sending marketing SMS. You should only import phone numbers for subscribers who have actively opted in to receive SMS messages from your business. Consult a legal professional for guidance specific to your jurisdiction.

    Can I import phone numbers without email addresses?

    Sender's import process uses email addresses as the primary subscriber identifier. Each row in your import file should include an email address along with the phone number to ensure the subscriber record is created or matched correctly.

    Can I assign imported subscribers to a group?

    Yes. During the import process, the Add subscribers to a group section lets you select one or more existing groups from the Choose groups dropdown, or create a new group by selecting Create a new group. This helps organize your SMS subscribers for targeted campaigns.

    What happens if I import a phone number for an existing subscriber?

    If the email address in your import file matches an existing subscriber, Sender updates that subscriber's record with the newly imported phone number. The existing subscriber data is not duplicated.

    How do I verify that the phone numbers were imported correctly?

    After importing, go to Subscribers → Subscribers and click on a recently imported contact. The subscriber profile will display the phone number under the SMS campaign section, along with its status. The Subscriber activity log will also show a "Phone set to [number] — Source: Import" entry confirming the import.

    Are there SMS sending restrictions by country?

    Yes. Some countries have specific carrier restrictions on sender IDs, content, or sending hours. Check Sender's SMS documentation or contact support for details about restrictions in your target countries.

  • SMS quiet hours and sending time restrictions

    This guide walks you through how to understand SMS quiet hours, comply with sending time restrictions, and use Sender's scheduling tools to send SMS campaigns at appropriate times.

    Where to Find This Feature

    In the Sender dashboard, go to: SMS campaigns

    You will see the SMS campaign library, which contains your drafted, scheduled, sending, and sent campaigns. The New campaign button at the top lets you create a new SMS campaign. Sending time settings are configured during the final step of campaign creation, called Review and schedule, where you choose when your campaign is sent.

    To manage your sender phone numbers and SMS message add-ons, go to: Account settings → SMS settings

    Steps to Configure SMS Sending Times and Respect Quiet Hours

    Step 1 — Understand SMS Quiet Hours

    Quiet hours are time windows during which sending marketing SMS messages is restricted or prohibited. Under the TCPA (Telephone Consumer Protection Act, a US federal regulation governing telemarketing communications), businesses cannot text customers before 8:00 AM or after 9:00 PM in the recipient's local time zone. Similar restrictions may apply in other jurisdictions under regulations like the GDPR or local carrier rules. Scheduling your SMS campaigns outside of these restricted windows helps you stay compliant and reduces the risk of complaints, opt-outs, and potential fines.

    Step 2 — Create Your SMS Campaign Content

    In the Sender dashboard, click SMS campaigns in the left sidebar, then click New campaign. On the Campaign settings page, enter a Campaign name, select a verified phone number from the Sender dropdown, and write your message in the Message text field. Enable the Add Opt-Out instructions toggle to include unsubscribe instructions. Enable Insert your organisation name to prepend your brand name to the message, which is recommended by U.S. carriers. Click Save and continue to proceed to the Recipients step, select your subscriber groups or segments, and then click Save and continue again to reach the final step.

    Step 3 — Schedule Your Campaign for a Compliant Sending Time

    On the Review and schedule step (labeled Confirm and send), you will see a summary of your campaign settings, subscriber count, estimated cost, and a message preview. To send at a specific time that respects quiet hours, click Schedule to send. A Schedule campaign dialog will appear with a calendar date picker and a Select time field. Choose a date and set the time to fall within the compliant sending window — between 8:00 AM and 9:00 PM in your recipients' local time zone. Click Schedule to confirm. Your scheduled campaign will appear in the SMS campaign list with the scheduled delivery date and time.

    Step 4 — Verify Your Scheduled Time Before Sending

    Before finalizing, review the scheduled date and time displayed in the campaign summary. Confirm that the sending time accounts for time zone differences if your subscribers are in multiple regions. If you need to send immediately and it is within the compliant window, you can click Send now instead. You can also click Send a test SMS from the message preview panel to verify the message content and delivery before launching the full campaign.

    SMS Compliance Requirements

    TCPA (Telephone Consumer Protection Act) — Applies to businesses sending SMS to recipients in the United States. The TCPA generally prohibits sending marketing text messages before 8:00 AM or after 9:00 PM in the recipient's local time zone. Sender's scheduling tools allow you to set a specific delivery time to help you stay within these windows.

    GDPR (General Data Protection Regulation) — Applies to businesses sending SMS to recipients in the European Union and European Economic Area. While the GDPR does not specify exact sending hours, it requires that marketing communications be sent only with explicit consent and in a manner that respects the recipient's rights. Some EU member states have additional rules restricting commercial messaging during certain hours or on certain days.

    Carrier-Level Restrictions — Mobile carriers in various countries may impose their own rules on when and how marketing SMS can be delivered. These can include restrictions on sending times, content filtering, and throughput limits. Violating carrier policies can result in message blocking or sender ID suspension. Check Sender's SMS documentation or contact support for details about restrictions in your target countries.

    Sender's SMS Policies — Sender requires that all SMS campaigns include opt-out instructions and recommends including your organization name in every message. Sender also requires a verified phone number or registered sender ID before you can send campaigns. These policies complement regulatory requirements and help protect your sending reputation.

    Always consult a legal professional for jurisdiction-specific advice on SMS sending time restrictions and compliance obligations.

    What Happens Next

    After scheduling your campaign, it will appear in the SMS campaigns list with a Scheduled status and the delivery date and time displayed alongside it.

    You can return to SMS campaigns at any time to view, edit, or cancel scheduled campaigns before they are sent.

    To verify everything is working correctly, use the Send a test SMS option on the Review and schedule step to send a test message to your own phone number before launching the campaign.

    Your scheduled SMS campaigns will also be visible in campaign reports after delivery, where you can track delivery status, failed messages, and other performance metrics.

    Common Issues

    SMS sent outside compliant hours → This happens when the scheduled time does not account for time zone differences between your account's time zone and your recipients' local time zones. Review your account time zone under Account settings → General settings → Time zone, and adjust your scheduled delivery time to ensure it falls within 8:00 AM–9:00 PM for all recipient regions.

    Campaign shows "No verified phone numbers have been found" → This occurs when no sender phone number has been verified or approved. Go to Account settings → SMS settings to check your phone number status. If your phone number shows In Progress, wait for verification to complete before creating a campaign.

    Scheduled campaign not sending at the expected time → This can happen if the time zone set in your Sender account does not match your intended delivery time zone. Confirm the time zone under Account settings → General settings and recalculate the schedule if your recipients are in a different region.

    Recipients report receiving messages at inconvenient times → This typically occurs when your subscriber list spans multiple time zones and you schedule a single send time. Consider segmenting your audience by region and scheduling separate campaigns for each time zone to ensure all messages arrive within compliant hours.

    FAQs

    What are SMS quiet hours? Quiet hours are time periods during which sending marketing SMS messages is restricted or prohibited by regulations. In the United States, the TCPA generally requires that marketing texts not be sent before 8:00 AM or after 9:00 PM in the recipient's local time zone. Other countries and carriers may have their own restrictions. Consult a legal professional for guidance specific to your jurisdiction.

    Does Sender automatically block SMS during quiet hours? Sender provides scheduling tools that let you control exactly when your campaign is sent. It is your responsibility to schedule campaigns at times that comply with applicable regulations. Use the Schedule to send feature on the Review and schedule step to set a delivery time within the compliant window for your audience.

    How do I schedule an SMS campaign in Sender? During campaign creation, complete the Settings and Recipients steps, then on the Review and schedule step, click Schedule to send. Select a date and time using the calendar and time picker in the Schedule campaign dialog, then click Schedule to confirm.

    What time zone does Sender use for scheduling? Sender uses the time zone configured in your account settings. You can check or update this under Account settings → General settings → Time zone. Make sure this setting aligns with the time zone you intend for your campaign delivery.

    What should I do if my subscribers are in multiple time zones? Segment your subscriber list by geographic region or time zone. Create separate campaigns for each segment and schedule each one to arrive within the compliant sending window for that region. This ensures all recipients receive your message during appropriate hours.

    Can I send an SMS campaign immediately instead of scheduling it? Yes. On the Review and schedule step, click Send now to deliver the campaign immediately. Before doing so, confirm that the current time falls within the compliant sending window for your recipients' time zones.

    Are there sending time restrictions outside the United States? Yes. Many countries have their own regulations governing when commercial SMS messages may be sent. Some EU member states, for example, restrict marketing messages during evenings, weekends, or public holidays. Carrier-level rules may also apply. Check Sender's SMS documentation or contact support for specific country restrictions, and consult a legal professional for compliance guidance.

  • SMS Limits by Plan

    This guide explains the SMS sending limits included with each Sender plan so you can choose the right plan and manage your SMS credits effectively.

    Where to Find This Feature

    In the Sender dashboard, go to: Account settings → Billing

    On the Billing page, you will see an SMS campaign section that displays three key metrics: your current SMS credit left balance, the number of Unique subscribers messaged during the current billing period, and the total SMS messages sent. You can also click Buy SMS credits to purchase additional credits, or click Change or renew plan to upgrade your plan for higher SMS limits.

    Steps to Check and Manage Your SMS Limits

    Step 1 — Confirm Your Current Plan Supports SMS

    Not all Sender plans include SMS. The Free Forever plan and the Pay as you go plan do not support SMS campaigns. To send SMS messages, you need a Standard, Professional, or Enterprise plan. To check your current plan, go to Account settings → Billing and look at the Your plan card in the top-left corner. If you are on a plan that does not support SMS, click Change or renew plan to upgrade.

    Step 2 — Review Your SMS Usage and Credit Balance

    On the Billing page, locate the SMS campaign section. This displays three values: your SMS credit left (the remaining monetary balance available for sending SMS), the Unique subscribers messaged count (distinct subscribers who received at least one SMS during this billing period, shown against your plan limit), and the SMS messages sent total. Monitor these values to avoid reaching your limits mid-campaign.

    Step 3 — Understand SMS Limits by Plan Tier

    SMS limits depend on which plan you are on and the subscriber tier you selected:

    Standard — Includes SMS messaging capability, but no free monthly SMS credits. You must purchase SMS credits separately by clicking Buy SMS credits on the Billing page. Your unique subscribers messaged limit matches your plan's subscriber tier (for example, 1,000 on a 1k-subscriber plan).

    Professional — Includes free monthly SMS credits that are automatically added to your account each billing period. The credit value scales with your subscriber tier (for example, $20/month on the 1k plan, $320/month on the 30k plan). Your unique subscribers messaged limit also matches your subscriber tier. Free SMS credits expire after one month and do not roll over.

    Enterprise — Includes everything in the Professional plan. Contact Sender's sales team for details on SMS credit allocations and custom limits.

    Step 4 — Purchase Additional SMS Credits if Needed

    If you run out of SMS credits or need more than your plan provides, go to Account settings → Billing and click Buy SMS credits. On the purchase page, select a credit package or enter a Custom amount. Use the SMS price calculator to check the cost per message for your destination country — SMS pricing is character-based and varies by country. Select your payment method and click Purchase to add credits to your account. Additional credits are available on both the Standard and Professional plans.

    SMS Compliance Requirements

    Character-based billing — Sender bills SMS messages based on character count. A standard SMS using GSM-7 encoding (the default character set for Latin-alphabet text messages) supports up to 160 characters per message segment. If your message exceeds 160 characters, it is billed as two or more SMS messages. Keep messages concise to control costs.

    Opt-out requirements — Every marketing SMS must include opt-out instructions such as "Reply STOP to unsubscribe." You can configure your default opt-out text in Account settings → SMS settings under SMS Message Add-ons. This is required by most carrier regulations and Sender's own SMS policies.

    TCPA (US) — The Telephone Consumer Protection Act requires prior express written consent before sending marketing text messages to US recipients. Collect consent through signup forms with a clear opt-in statement. Consult a legal professional for jurisdiction-specific guidance.

    GDPR (EU) — The General Data Protection Regulation requires a lawful basis (typically explicit consent) for processing personal data, including phone numbers, for marketing purposes. Ensure your SMS consent collection process meets GDPR requirements. Consult a legal professional for guidance specific to your situation.

    Carrier restrictions — Some countries and carriers impose restrictions on sender IDs, message content, or sending hours. SMS pricing also varies by destination country. Check the SMS price calculator on the Buy SMS credits page or contact Sender support for details about restrictions in your target countries.

    Always consult a legal professional for advice specific to your jurisdiction and use case.

    What Happens Next

    After confirming your plan supports SMS, check your SMS credit left balance on the Billing page to ensure you have enough credits before sending a campaign.

    If you are on the Professional plan, your free monthly SMS credits will appear automatically at the start of each billing period — remember that unused credits expire after one month.

    To verify your setup is working correctly, send a test SMS to your own phone number from the SMS campaigns section before launching a campaign to a larger audience.

    You can monitor your SMS usage at any time by returning to Account settings → Billing and reviewing the SMS campaign section.

    Common Issues

    SMS campaigns option is not available → Your account is on the Free Forever or Pay as you go plan, neither of which supports SMS. Upgrade to a Standard or Professional plan under Account settings → Billing → Change or renew plan.

    SMS credit balance is zero or too low → Your free monthly credits (Professional plan) may have expired, or you have used all purchased credits. Go to Account settings → Billing and click Buy SMS credits to add more. Professional plan credits expire after one month and do not carry over.

    Unique subscribers messaged limit reached → You have sent SMS messages to the maximum number of distinct subscribers allowed by your plan tier during this billing period. To increase this limit, upgrade to a higher subscriber tier under Account settings → Billing → Change or renew plan.

    Message billed as multiple SMS → Your message exceeded 160 characters (GSM-7 encoding), so it was split into multiple message segments. Each segment counts as a separate SMS. Shorten your message or account for the additional cost when budgeting credits.

    SMS price varies by country → SMS pricing depends on the destination country. Use the SMS price calculator on the Buy SMS credits page to check the per-message cost for your target country before purchasing credits.

    FAQs

    Which Sender plans include SMS? SMS campaigns are available on the Standard, Professional, and Enterprise plans. The Free Forever and Pay as you go plans do not include SMS.

    Does the Professional plan include free SMS credits? Yes. The Professional plan includes a monthly SMS credit allocation that scales with your subscriber tier. For example, the 1k-subscriber Professional plan includes $20/month in free SMS credits. These credits expire after one month and do not roll over to the next billing period.

    Does the Standard plan include free SMS credits? No. The Standard plan enables SMS messaging, but you must purchase SMS credits separately through Account settings → Billing → Buy SMS credits.

    What is the unique subscribers messaged limit? This is the maximum number of distinct subscribers you can send at least one SMS to during a single billing period. The limit matches your plan's subscriber tier (for example, 1,000 on a 1k-subscriber plan, 30,000 on a 30k-subscriber plan).

    How is SMS pricing calculated? SMS pricing is character-based and varies by destination country. A single SMS supports up to 160 characters using GSM-7 encoding. Messages longer than 160 characters are billed as multiple SMS. Use the SMS price calculator on the Buy SMS credits page to estimate costs for your target country.

    What SMS credit packages are available? Sender offers preset credit packages as well as a Custom amount option. You can purchase credits on the Buy SMS credits page under Account settings → Billing.

    Do unused SMS credits expire? Free monthly SMS credits included with the Professional plan expire after one month. Separately purchased SMS credits may have different expiration terms — check your Billing page for details on your current credit balance.

    How do I check my remaining SMS credits? Go to Account settings → Billing and look at the SMS campaign section. Your remaining balance is displayed under SMS credit left.

  • SMS character limits and message segmentation

    This guide explains how SMS character limits and message segmentation work in Sender, and how they affect your campaigns and credit usage.

    Where to Find This Feature

    In the Sender dashboard, go to: SMS campaigns

    Click New campaign to open the Campaign settings page. The Message text section displays a character counter below the text area in the format X/160 - 1 SMS. This counter updates in real time as you type and reflects the current encoding mode, character count, segment limit, and total number of SMS segments your message will use.

    Steps to Understand and Manage SMS Character Limits

    Step 1 — Check the character counter while composing your message

    In the Message text field, begin typing your SMS content. The counter below the text area displays your current character count, the per-segment limit, and the number of SMS segments. For standard text, it shows a format like 24/160 - 1 SMS. If your message stays within 160 characters using GSM-7 encoding (standard letters, numbers, and common punctuation), it sends as a single SMS segment and uses one credit.

    Step 2 — Monitor how the counter changes for longer messages

    When your message exceeds 160 characters, the counter automatically adjusts to show multi-segment values. For example, it may display 82/153 - 2 SMS. The per-segment limit drops from 160 to 153 because 7 characters in each segment are reserved for concatenation headers that allow the recipient's device to reassemble the full message. Each additional segment of up to 153 characters adds one more SMS credit to the total cost of that message.

    Step 3 — Watch for Unicode encoding when using emojis or special characters

    If you add an emoji from the emoji picker (the smiley icon beside Custom fields) or type special characters outside the GSM-7 character set, the encoding switches to Unicode. The counter changes to reflect the reduced limit — for example, 23/70 - 1 SMS. A single Unicode SMS segment supports only 70 characters. If a Unicode message exceeds 70 characters, it splits into segments of 67 characters each (3 characters per segment are used for concatenation headers).

    Step 4 — Account for opt-out text and organisation name in your character count

    Enabling Add Opt – Out instructions appends "Reply STOP to optout" to your message, and enabling Insert your organisation name prepends your brand name before the message content. Both options add characters that count toward the segment limit. The character counter updates automatically when you toggle either option. Check the counter after enabling these settings to confirm your message still fits within your intended number of segments.

    Step 5 — Preview and test before sending

    The Message preview panel on the right side of the Campaign settings page shows how your message appears on a device, including any appended opt-out text or prepended organisation name. Click Send a test SMS to deliver the message to a phone number and verify its content, length, and segmentation before sending to your full audience.

    Message Writing Guide

    GSM-7 character limit — A single SMS segment supports up to 160 characters when using standard GSM-7 encoding. GSM-7 includes Latin letters, digits, and common punctuation. Stay within this set to maximize the characters available per segment.

    Multi-segment messages (GSM-7) — Messages longer than 160 characters split into segments of 153 characters each. The remaining 7 characters per segment are used for concatenation headers so the recipient's phone can reassemble the full message in order.

    Unicode encoding — Using emojis, accented characters outside GSM-7, or characters from non-Latin scripts switches the message to Unicode encoding. A single Unicode segment holds 70 characters. Multi-segment Unicode messages use 67 characters per segment, with 3 characters reserved for concatenation headers.

    Personalization variables — Click Custom fields below the Message text area to insert variables like {{ firstname }}, {{ lastname }}, or {{ email }}. The variable tag itself (e.g., {{ firstname }}) counts toward the character limit at its full tag length, but the actual characters used at send time depend on each subscriber's data.

    Opt-out text — Enabling Add Opt – Out instructions appends unsubscribe text to every message. This text counts toward your character and segment totals, so factor it into your message length when composing.

    Organisation name — Enabling Insert your organisation name prepends your brand name before the message body. These additional characters also count toward the segment limit shown in the counter.

    Link shortening — The Automatically shorten links checkbox (enabled by default) replaces full URLs with shortened versions. Shortened links use fewer characters, which helps keep your message within a single segment.

    Campaign Management Actions

    Edit a draft campaign — From the SMS campaign list, click the edit icon (pencil) next to a draft campaign to reopen it in the Campaign settings editor. You can modify the message text, recipients, and scheduling before sending.

    Duplicate a campaign — Open the actions menu (dropdown arrow) next to a campaign and select Duplicate. A copy is created in Draft status with the same content and settings, ready to edit and send as a new campaign.

    Delete a campaign — Open the actions menu next to a campaign and select Delete. This removes the campaign from your list. Deleted campaigns cannot be recovered.

    Save as draft — Click I'll finish later at any point during the campaign creation workflow to save your progress and return to it later. The campaign appears in the SMS campaign list with a Draft status.

    Campaign Tips

    Keep messages under 160 characters — Staying within the single-segment GSM-7 limit of 160 characters uses only one SMS credit per recipient and avoids segmentation.

    Avoid emojis when character count matters — A single emoji switches the entire message to Unicode encoding, reducing the limit from 160 to 70 characters per segment. Remove emojis if you need more space for text content.

    Test personalization variables — Variable tags like {{ firstname }} may expand to different lengths for each subscriber. Use Send a test SMS to verify the message reads correctly and does not split unexpectedly when real subscriber data replaces the tags.

    Factor in opt-out and organisation text — If you enable Add Opt – Out instructions or Insert your organisation name, check the updated character counter before finalizing. These additions may push your message into an additional segment.

    Use templates for recurring messages — Click Save as template after writing a message you plan to reuse. When creating a new campaign, click Use a template to load a saved message and avoid rewriting content from scratch.

    Common Issues

    Message splits into more segments than expected → This typically happens when emojis or special characters trigger Unicode encoding, which reduces the per-segment limit from 160 to 70 characters. Remove non-GSM-7 characters and check the counter to confirm the encoding returns to X/160.

    Character counter shows a higher number than the visible text → Enabled toggles for Add Opt – Out instructions or Insert your organisation name add hidden characters that count toward the total. Disable these toggles temporarily to see the count for your message text alone.

    Personalization variables increase segment count → Variable tags like {{ firstname }} occupy a fixed number of characters in the editor, but the actual subscriber data inserted at send time may be longer. If a subscriber's first name is 15 characters, it replaces the tag and may push the message into an additional segment. Write shorter messages to leave room for variable expansion.

    Message preview does not match expected output → The Message preview panel reflects your current message text, opt-out instructions, and organisation name in real time. If the preview looks incorrect, verify that the correct toggles are enabled and that no unintended characters were pasted into the Message text field.

    FAQs

    How many characters can an SMS message contain? A single SMS segment supports 160 characters using standard GSM-7 encoding. If your message exceeds 160 characters, it is split into multiple segments of 153 characters each (7 characters per segment are used for concatenation headers). Using emojis or special characters switches to Unicode encoding, which reduces the limit to 70 characters per single segment or 67 characters per segment in multi-segment messages.

    How does the character counter work in Sender? The counter below the Message text field displays the format characters/limit - segments SMS. For a standard message, it shows values like 24/160 - 1 SMS. When the message exceeds the single-segment limit, it updates to reflect the multi-segment per-segment limit, such as 82/153 - 2 SMS. If Unicode characters are detected, the limit adjusts to X/70 for a single segment.

    Can I personalize SMS messages with subscriber data? Yes. Click Custom fields below the Message text area to open the field selector. Choose from available fields such as First name, Last name, Email, Phone number, or Birthday. Sender inserts the variable tag (e.g., {{ firstname }}) into your message and replaces it with the subscriber's actual data at send time.

    Does opt-out text count toward my character limit? Yes. Enabling Add Opt – Out instructions appends text such as "Reply STOP to optout" to your message. These characters are included in the counter and count toward your segment total. Check the counter after enabling this toggle to verify your message still fits within the intended number of segments.

    How are SMS credits charged for multi-segment messages? Each SMS segment counts as one credit. A message under 160 characters (GSM-7) uses one credit. A message that splits into two segments uses two credits per recipient. Unicode messages use more credits because the lower character limit per segment means more segments are needed to deliver the same amount of text.

    Can I duplicate an existing SMS campaign? Yes. From the SMS campaign list, open the actions menu (dropdown arrow) next to the campaign and select Duplicate. A copy is created in Draft status with the same content and settings, ready to edit and send.

  • Compliance and Opt-In Rules

    This guide walks you through the key compliance requirements and opt-in rules you need to follow before sending SMS messages in Sender for the first time.

    Where to Find This Feature

    In the Sender dashboard, go to Account settings → SMS settings.

    On this page, you will see the Phone numbers table listing your registered sender IDs with their use case, status, and date added. Below it, the SMS Message Add-ons section displays your Organizational prefix, Opt-out text, and Opt-out link text fields — the core compliance settings that are appended to your SMS messages.

    Steps to Set Up SMS Compliance & Opt-In

    Step 1 — Collect explicit consent from subscribers

    Before sending any SMS, you must have explicit opt-in consent from each recipient. This means the subscriber actively agreed to receive SMS messages from your business — pre-checked boxes or implied consent do not qualify.

    Use Sender's Forms feature to create signup forms that include a clear SMS opt-in statement, such as "I agree to receive marketing text messages from [Your Business]." Make sure the phone number field captures numbers in international format with the country code (e.g., +1 for the US, +44 for the UK). After publishing the form, subscribers who opt in will appear in your Subscribers list with an Active SMS status.

    Step 2 — Configure your opt-out message settings

    Go to Account settings → SMS settings and scroll to the SMS Message Add-ons section. You will see three fields:

    Organizational prefix — Enter your business or brand name. This text is added to the beginning of every SMS so recipients know who is messaging them.

    Opt-out text — Enter opt-out instructions that include the word "STOP," such as Reply STOP to opt-out. This field is required and must contain "STOP" in the message.

    Opt-out link text — Enter unsubscribe link text, such as Unsubscribe: {{unsubscribe_link}}. This provides an additional way for recipients to opt out via a clickable link.

    Click Update to save your changes.

    Step 3 — Review prohibited content and sender ID compliance

    When registering a sender ID in Sender (via Account settings → SMS settings → Add phone number), you will see the TCPA & CTIA compliance notice. This outlines that explicit consent is required before sending SMS to US subscribers and lists content categories that are prohibited on Sender:

    S.H.A.F.T. content — Sexual, hateful, alcohol, firearms, or tobacco-related content.

    Drugs & vaping — CBD, vaping, cannabis, and related products or content.

    Gambling — Betting, lotteries, gaming for money, and related content.

    High-risk finance — Loans, debt relief, investments, tax relief, and work-from-home offers.

    Ensure your SMS content does not fall into any of these restricted categories. Violations may result in message blocking or account suspension.

    Step 4 — Verify subscriber SMS status and phone number format

    Go to Subscribers in the left sidebar. Use the SMS status filter at the top of the subscriber list to check the status of your SMS contacts. Available statuses include Active, Bounced, Unsubscribed, Reported spam, and Non-subscribed.

    Click on any subscriber to open their profile. You will see separate sections for Email campaign and SMS campaign, each with its own status indicator. Confirm that the subscriber's phone number is stored with the correct country code prefix (e.g., +370 638 31693) and that their SMS campaign status shows Active before including them in an SMS send.

    SMS Compliance Requirements

    TCPA (Telephone Consumer Protection Act) — Applies to SMS recipients in the United States. Requires express written consent before sending marketing text messages. Sender displays a TCPA compliance notice during sender ID registration and requires you to confirm that you have obtained subscriber consent.

    CTIA (Cellular Telecommunications Industry Association) guidelines — Industry standards enforced by US carriers. CTIA guidelines prohibit certain content categories (S.H.A.F.T., drugs, gambling, high-risk finance) and require that every marketing SMS includes opt-out instructions. Sender enforces these restrictions through its SMS Message Add-ons settings, which require the word "STOP" in your opt-out text.

    GDPR (General Data Protection Regulation) — Applies to recipients in the European Union and European Economic Area. Requires a lawful basis (typically explicit consent) for processing personal data, including phone numbers used for SMS marketing. Subscribers must be able to withdraw consent easily at any time.

    Sender's own SMS policies — Sender requires an organizational prefix on every message, a valid opt-out mechanism in every SMS, and prohibits the content categories listed during sender ID registration. These policies apply regardless of the recipient's location and are enforced through the SMS Message Add-ons configuration on the SMS settings page.

    Always consult a legal professional for advice specific to your jurisdiction and use case. The information above is general guidance and does not constitute legal advice.

    What Happens Next

    After configuring your compliance settings, send a test SMS to your own phone number to verify that the organizational prefix, message content, and opt-out text all display correctly.

    You can manage your opt-out text and organizational prefix at any time by returning to Account settings → SMS settings and updating the SMS Message Add-ons section.

    Subscribers who reply "STOP" will automatically have their SMS status changed to Unsubscribed, which you can monitor using the SMS status filter on the Subscribers page.

    With your compliance settings in place, you are ready to create and send SMS campaigns from the SMS campaigns section in the left sidebar.

    Common Issues

    Opt-out text rejected → The Opt-out text field requires the word "STOP" to be included in the message. If your text is rejected, check that it contains "STOP" (e.g., Reply STOP to opt-out) and click Update to save.

    Subscriber SMS status shows Non-subscribed → This means the subscriber does not have a valid phone number on their profile or has not opted in to SMS. Open the subscriber's profile, add a phone number in international format with the country code, and confirm their SMS consent.

    Sender ID status shows In Progress → After registering a new sender ID, it may take time for carrier verification to complete. The status will update to Active once approved. Do not send campaigns until the status changes from In Progress.

    Prohibited content blocking → If your SMS messages are blocked, review your content against the restricted categories (S.H.A.F.T., drugs, gambling, high-risk finance). Remove any prohibited content and resubmit your message.

    Phone number format errors → Phone numbers must include the full country code prefix in international format (e.g., +1 for the US, +44 for the UK). If subscribers are not receiving messages, verify their phone numbers include the correct country code on their subscriber profile.

    FAQs

    What is a sender ID?

    A sender ID is the name or phone number that appears as the sender when recipients receive your SMS. In Sender, you can choose between a Toll-free number (a +18xx format phone number available in the US and Canada) or an Alphanumeric ID (your brand name, available outside the US and Canada, one-way messaging only). You select your sender type when clicking Add phone number on the SMS settings page.

    Do I need consent to send SMS messages?

    Yes. SMS regulations like TCPA (US) and GDPR (EU) require explicit consent from recipients before sending marketing SMS. Collect consent through signup forms with a clear opt-in statement. Sender displays a compliance notice during sender ID setup as a reminder. Consult a legal professional for guidance specific to your jurisdiction.

    What should I include in every SMS message for compliance?

    Every marketing SMS should include your business name (set via the Organizational prefix field) and opt-out instructions containing the word "STOP," such as "Reply STOP to opt-out." These are configured in the SMS Message Add-ons section under Account settings → SMS settings. Sender appends these automatically to your messages.

    What phone number format does Sender require?

    Phone numbers must be stored in international format with the country code prefix (e.g., +1 for the United States, +44 for the United Kingdom). You can verify the format on each subscriber's profile under the SMS campaign section, which displays the phone number with a country flag indicator.

    How do I check a subscriber's SMS opt-in status?

    Go to Subscribers and use the SMS status filter dropdown at the top of the list. You can filter by Active, Bounced, Unsubscribed, Reported spam, or Non-subscribed. Only subscribers with an Active SMS status should receive your marketing SMS messages.

    What content is prohibited in SMS messages sent through Sender?

    Sender prohibits S.H.A.F.T. content (sexual, hateful, alcohol, firearms, tobacco), drugs and vaping products, gambling-related content, and high-risk finance content (loans, debt relief, investments, tax relief, work-from-home offers). These restrictions are displayed during sender ID registration and align with CTIA carrier guidelines.

    Are there SMS sending restrictions by country?

    Yes. Some countries have specific carrier restrictions on sender IDs, content, or sending hours. For example, Toll-free numbers are only available in the US and Canada, while Alphanumeric IDs are available outside those countries. Check Sender's SMS documentation or contact support for details about restrictions in your target countries.