Set Up a Text Broadcast (SMS Blast) campaign

A Text Broadcast campaign (also called an SMS Blast or Text Blast) lets you send a single message in bulk to your contact lists, personalize it for each person with merge tags, and set up keyword-based auto-replies so common responses are handled automatically.

Use a Text Broadcast when you want to:

• Announce an event, share a donation link, or send a reminder to a large audience in one go.
• Reach people where they actually look — texts are read far more reliably than email.
• Personalize at scale: merge tags drop each contact's own details into the message, which typically earns higher response rates and engagement than a generic blast.
• Handle replies without staffing an inbox — keyword auto-replies answer common responses instantly, and you can jump in manually for anything else.

By the end of this article, you'll have a scheduled campaign that sends your message to every contact on your list, retries failed sends, and notifies you by email when people reply.

Before you start

• You'll need: a CallHub account with admin/collaborator access to create campaigns.
• A contact list containing contacts with mobile numbers. You can add more than one list to a single campaign.
• A sending number: you can rent one during setup.
• Time: setup takes about 10 minutes.

⚠ Sending to the US? You need a 10DLC or Toll-Free number. US carriers require business texting to go through a registered 10DLC (10-digit long code) or Toll-Free number. Set this up before creating your campaign — unregistered numbers risk carrier filtering, blocked messages, and extra fees. Registration approval can take a few business days, so plan ahead. See Registering a 10DLC number or Registering a Toll-Free number to get started.

⚠ Message consent. Send broadcasts only to contacts who have opted in to receive texts from you. Shortcode messaging in particular is designed for opt-in audiences. Texting people without consent can violate messaging regulations and get your numbers blocked.

ⓘ NOTE — Sender ID availability. By default, Sender ID is available only in limited countries. Contact Support to check whether your country supports Sender IDs before you plan a campaign around one.

Create SMS Broadcasting Campaign 

Create the campaign and add contacts

On your dashboard, under Text Broadcast, click Create.

Start a new Text Broadcast from your dashboard. A mobile preview appears alongside setup so you can see exactly what your contacts will receive.

Enter a name for your campaign.

Add the contact list you want to text. Every contact needs a mobile number.

ⓘ You can add multiple contact lists to one campaign.

Choose the number your contacts will see

The number (Caller ID) is what appears on your contacts' phones when your message arrives. On the numbers step, pick one of two options:

1. Automatically Rent a Number — choose the country you want to rent a number in, and CallHub rents one for the campaign.
2. Validated and previously rented number — select a previously rented number on your account from the dropdown. (Validated numbers can't be used for texting, so only rented numbers will work here.) Rent a new number or reuse one already on your account.

ⓘ Sending Messages in the US? If you're sending to US contacts, use your registered 10DLC or Toll-Free number here.

ⓘ Number missing from the dropdown? If a rented number doesn't appear, it's currently in use by a running campaign. Stop that campaign first, then the number becomes available to reuse.

ⓘ By default, Sender ID is available in limited countries. Please contact Support to check if your country supports Sender IDs.

Write your message

1. In the Script section, type your message.
2. To personalize your message, click Personalize and choose from the merge tags available for your campaign. Each contact receives the message with their own details filled in, and personalized messages consistently earn higher response rates. For the full list of merge tags and how they work, see How to personalize conversations in CallHub.
3. Insert merge tags to personalize each message automatically. 
4. (Optional) Add font styles (like 𝔽𝕠𝕟𝕥 𝕤𝕥𝕪𝕝𝕖𝕤, bold, or italics) and emojis to make your message friendlier and more engaging.

⚠ Styling affects billing. If you use font styling, check the Convert message to MMS option. Otherwise, the styled text splits into multiple SMS segments, and you're charged for each one. With the option enabled, you're charged for 1 MMS per message instead. Incoming messages are billed at standard SMS and MMS rates.

ⓘ SMS length limits. A standard SMS holds at most 160 ASCII characters or 70 Unicode characters. Go over the limit, and you're charged for 2 SMS.

Set up automated keyword replies

1. Enable Automated Replies.
2. Enter the keyword you want to watch for (for example, "INFO").
3. Enter the response the system should send back automatically.
4. When a contact texts your keyword, CallHub replies instantly, no manual work needed.

Configure delivery settings

In the Settings section, fill in:

1. Email Replies — the email address that receives a notification for every response your campaign gets.
2. Max Retries — how many times CallHub retries a failed or unsent message per contact. Messages can fail if a contact is unreachable at send time, so retries help your message actually land.
3. Time Between Retries — the delay, in seconds, before a failed message is retried. Retries give unreachable contacts a second chance to get your message.

ⓘ You can't reply to contacts from the notification emails. To respond, log in to your dashboard (see Reply to incoming responses below).

Schedule the campaign

1. Set the Start and Finish dates.
2. Choose the days the campaign will operate.
3. Set the daily operating hours.

ⓘ You can edit the operational days and hours later if your plans change.

Reply to incoming responses

Auto-replies handle your keywords, but you can also respond to any contact manually as the account admin:

1. Log in to your CallHub account.
2. Go to Campaigns and click on your campaign.
3. Open Responses.

4. Choose the contact and click the chat. The window expands into a text editor. Reply to any contact directly from the dashboard

   

5. Reply to any contact directly from the dashboard. Type your response and click Reply.

   

FAQs

Why isn't my rented number showing in the dropdown? 
It's being used by a campaign that's currently running. Stop that campaign, and the number becomes available to select.

Will I be charged extra for long or styled messages? 
Yes, unless you plan for it. A standard SMS is 160 ASCII or 70 Unicode characters — exceeding that bills as 2 SMS. Styled text should be sent with Convert message to MMS checked, so you're billed for 1 MMS instead of multiple SMS segments.

Can I reply to contacts from the email notifications? 
No. Notification emails are read-only. Reply from the dashboard under Campaigns > your campaign > Responses.

Can I use a Sender ID in my country? 
Sender ID is available only in limited countries by default. Contact Support to confirm availability for yours.