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Bulk SMS Campaigns: How to Run The Perfect Message to Your Audience

Published: Mar 29, 2024

Why should you go for bulk SMS campaigns? While we have all heard the ‘98%’ opening rate about SMS, this slightly dodgy statistic should not be the only reason why a bulk SMS campaign must be part of your arsenal (though, of course, it is true that people check their messages a lot more than their emails). 

By combining an SMS with automated replies, peer-to-peer conversations, scheduled reminders, and personalization, you can essentially have an intimate chat with thousands of supporters, customers, or voters in an instant.  

In a world where it is easy to lose your message in a sea of spam, this is the best way to speak directly to a huge audience without being ignored. Here’s all you need to know to get you started, and the unique advantages that CallHub offers your bulk SMS campaign. 

What is bulk SMS or mass texting?

Bulk SMS (Short Message Service) enables organizations to send large numbers of text messages simultaneously to groups of contacts – who have opted in for the communication. 

These messages are typically sent from an online platform to 

  • promote campaigns and fundraisers 
  • send notifications 
  • Broadcast reminders for events. 

Bulk SMS also allows urgent messages to be broadcast quickly. 

Mass texting allows campaigns to reach out to their target audience quickly and efficiently in a cost-effective manner. Platforms like CallHub offer features like scheduling messages, personalization, delivery reports, and segmentation to tailor messages according to recipients’ preferences and demographics.

How to do bulk SMS marketing?

Bulk SMS marketing involves several steps to plan, execute, and measure the effectiveness of your campaign. 

Step one is to get opt-ins for messages from your target audience to comply with regulations like GDPR (General Data Protection Regulation) and TCPA (Telephone Consumer Protection Act). You can collect phone numbers through website opt-in forms, in-store sign-ups, events, or other channels.

Once you have the contacts opted in, your following campaigns could include bulk SMS communications. Remember to:

  • Craft concise, engaging, and relevant messages.
  • Include a clear call-to-action (CTA).
  • Include links related to the CTA (as relevant) to reduce friction before taking action.

Adhere to regulations and guidelines governing SMS marketing, such as obtaining recipient consent, providing opt-out options, and maintaining compliance with spam laws. Failure to comply with regulations can result in legal consequences and damage your brand reputation.

From here, you need a reputable bulk SMS service provider that offers the features and capabilities you need for your campaign. CallHub offers advantages like message delivery rates, scalability, pricing, customer support, and regulation compliance. 

Basic best practices for bulk SMS marketing

Obtain explicit consent: Ensure you have obtained explicit permission before sending SMS messages. This helps you comply with regulations such as GDPR and TCPA and builds trust with your audience.

Important:  Your first message to new contacts must identify the sender, set expectations on the nature and frequency of messages, and state simple opt-out mechanisms. Typically, this first message would be a prompt when they opt-in via text. However, if you are collecting opt-ins from elsewhere, this would ideally be your first bulk SMS to your newly acquired contacts.

Template: Hi {first_name}, this is Vin from the Diesel campaign. Glad to have you here. We will send event notifications to you every month. Send CANCEL to stop messages. 

Provide opt-out options: Include clear instructions on how recipients can opt out of receiving further SMS messages from you. Make it easy for recipients to unsubscribe if they no longer wish to receive your messages, and promptly honor their requests.

CallHub will automatically unsubscribe contacts who respond with keywords like STOP, CANCEL, UNSUBSCRIBE, etc. In our system, these phone numbers are added to a DNC list to avoid sending SMS messages in future campaigns.

Political text messages can be sent without the intended recipient’s prior consent if the message’s sender does not use auto-dialing technology to send such texts and instead manually sends them one at a time.

Keep messages concise: SMS messages have a character limit, typically 160 characters. Keep your messages concise, clear, and to the point. Focus on conveying your message effectively within the limited space to capture recipients’ attention quickly.

Personalize messages: Use the recipient’s name or other personalized information to make your messages more engaging and relevant. Moreover, carriers will flag identical messages and may even affect your delivery rate (unless you have a 10DLC number). Adding personalized fields will make each text message unique and stop this flagging.

CallHub allows you to personalize your messages with the help of merge tags. Our default tags include first and last name, address, and contact number information. You can also add more custom fields (e.g., supporter levels or donor levels) on CallHub or import them from your CRM.   

Include a clear call-to-action (CTA): Every SMS message should have a clear and compelling CTA that prompts recipients to take a desired action, such as donating, visiting a website, or replying to the message.

Timing matters: Consider the timing of your messages to maximize their impact. Track the performance of all your bulk SMS campaigns while experimenting with the timing. While there are some studies on the best and worst time to send text blasts, test your campaigns for yourself.

Legally, you must send your messages between 8 am and 9 pm only. CallHub’s systems will pause your campaign to ensure your messages only go out during legal hours. 

Best time to send bulk SMS? 

Using some common sense and considering the target audience, you should be able to customize a time that works best for you easily. For example, if your campaign is appealing to white-collar workers, Monday morning at 9 a.m. may not be the best time to ask for donations. And you must consider time zones. What is 9 a.m. in the east will be 8 a.m. in Central time. 

Here are some quick tips


Between 9 a.m. and 12 p.m. and between 5 p.m. and 9 p.m.

People tend to check their messages before starting work, before going for lunch, before heading home, and after dinner. The ideal time would be between 7 p.m. and 9 p.m. when most people would be home after work. 


Between 10 a.m. and 12 p.m. on Saturdays and Sundays and between 4 p.m. and 7 p.m. on Sundays.

You aim for ‘before weekend plans begin’ on a Saturday and ‘after the weekend is wrapped up’ on a Sunday. 

Use automated text scheduling to ensure all messages are sent at the optimum time. You can schedule your messages while setting up your texting campaign in CallHub.

Advanced best practices for successful bulk SMS marketing

Use a 10DLC number

10 Digit Long Code (10DLC) numbers are sanctioned by mobile carriers for application-to-person messaging (A2P). Compared to earlier local long codes used for campaigns, 10DLC can support higher volumes of text messages.

A2P messaging means using software like CallHub to send text messages instead of sending them from your mobile phone. 

A new organization called The Campaign Registry (TCR) now exists to help register 10DLC numbers. These organizations are vetted, and TCR assigns them a ‘trust score’. This allows the carriers to increase message throughput for solicited messages and offer better deliverability. 10DLC makes it much harder for bad actors to send unwanted text messages through carriers. 

Here are some advantages: 

  • 10DLC numbers are approved for A2P texting by carriers. You are minimizing the small chance of not reaching contacts.
  • 10DLC numbers get higher messages per second (MPS) than previously used long code numbers. This will vary based on the trust score (Low, Medium, High) that the TCR assigns a campaign.
  • With consent being key to 10DLC, you will get better response rates for your campaigns (and thereby reduce costs).

CallHub is an official CSP (Communication Service Provider) partner of TCR. We can register your brand, campaigns, and use cases and get you 10DLC numbers that you can use on CallHub’s texting campaigns.

It’s as simple as registering with CallHub and filling out a form.  Post this; you can rent 10DLC-enabled numbers when you set up a campaign. 

Segment your contact lists for better targeting

Personalization is key. Consider some facts from this 2021 McKinsey & Company study

  • 71% “expect personalized interactions.” 
  • 76% said they were “frustrated” when there was no personalization in the communication. 
  • Companies saw a 40% increase in results from personalization. 

What does personalization mean? 

  • Messages are addressed to the contact by name. 
  • Messages acknowledge if the contact has interacted with this campaign (or business) before and reference the last message. 
  • Messages acknowledge the contact’s location, preference, or previous answers to questions.
  • Messages are triggered by the contact’s behavior – a response, no response, a link clicked, etc. 

Advanced segmentation of your contact lists considers these factors. While you start with a complete “universe” list, your list should be segmented with every campaign. Depending on your use case, you could segment lists based on the activity (or inactivity) of a contact, the nature of their responses, or demographics (relevant to your campaign).

However, maintaining and multiplying contact lists perpetually may be overwhelming. Ultimately, you want to take personalized actions for each contact, hence the segmentation. We have another solution.

You can easily set this up using CallHub’s WorkFlows – using trigger words in the replies of contacts to automatically send a second message at a scheduled time on a later date. 

  • Updates list: Messages that inform the contact about actions taken since the first message. Again, you can automate this process at a scheduled time.  
  • Location-specific information: Messages are regularly sent to inform the contact about events, meetings, offers, donation drives, etc., being held in their area. 
  • Cause-specific list: This is the same as the location-specific list, except this is for a particular issue, cause, product, etc., that the contact expressed interest in. 

Automate your bulk SMS marketing campaigns

With automated text messaging, you can avoid operating a large part of your texting campaigns manually – not to mention having to remember and send out follow-up texts at the right time. 

Automating your campaigns reduces the time, effort, and resources required to communicate with your contacts—and is significantly cheaper. Messaging costs an average of $1-$5 per interaction, but automation can bring it down to 25 cents.

Critically, scheduled text broadcasts send time-sensitive information or promotions – like a text to your supporters reminding them of an upcoming event. You can create a campaign in advance and schedule it a day before the event. 

With CallHub, you can choose the time for the message to go out and set up operational hours for your campaign. 

You can also use auto-replies to have conversations in real-time. You can enable ‘Automatic Replies’ when setting up a texting campaign, add the trigger word, and reply on the spot.

For example, if you ask for an ‘RSVP’ in the first message and someone replies with ‘RSVP, ‘ a trigger will auto-reply immediately with details about the event and where to register, and WorkFlow will send a scheduled text to remind them of the event a day before the event.  

Use mass texting as a way for data collection

Data is the lifeblood of the modern political campaign. You need it to maximize volunteer time, to use limited financial resources best, and to encourage voters to support your candidate or cause. Data collection will be key to your campaign.

You can collect data when a contact signs up or opts in via text-to-join campaigns. Based on your set-up, you can send an automated message asking for specific details, such as their name, email address, or other relevant information. 

As the contact responds to the messages with the requested information, the data syncs back to your CRM, giving you a high-quality contact list to start contacting. This even lets you frame follow-up questions based on this data.

When not to use bulk SMS marketing?

When you don’t already have consent 

This should be self-evident—do not message people without their consent. However, there are legal regulations on this, so if you break the law, you can be fined heavily (upto $500 per message). So, it is best to only send messages to those who agree. 

Even in a ‘worst case’ scenario, sending messages without consent will not achieve your goals since it naturally results in very low responses, or you get marked as spam. 

When you want to talk, not broadcast

Bulk SMS is good for sending a quick one-way message but not useful if you want to converse with your audience, collect more data, or convince them about your business or campaign. 

You need ‘peer-to-peer’ (P2P) texting, through which your staff or volunteers can converse with whoever responds. Use CallHub’s peer-to-peer texting platform with advanced features to contact voters, collect data, drive action, raise funds, etc.

In a peer-to-peer texting campaign, a campaign manager uploads a contact list and assigns a batch of contacts to each volunteer. As contacts respond to the common initial text message, agents reply to them using templates or send a custom message and have one-to-one conversations with them.

Getting people to take action, like calling their rep or signing a petition, is made easier by having a volunteer answer queries and have an actual back-and-forth conversation with them.

PS: With P2P texting, one volunteer can text with multiple contacts. This allows you to handle larger contact lists with fewer agents.

When your messages are too long 

Aim for messages that are no more than 160 characters long. Short, concise messages are easy to read and respond to. Also, crucially, if the messages are too long, they are automatically broken into multiple messages, each one of which is billed. 

Since the cost of sending one SMS (in the US) is $0.034, sending a message broken into three segments will be charged at $0.034 x 3 = $0.102.

While creating a campaign, you can type in your message under Script. CallHub will show the number of characters remaining while you type. When you cross the 1 SMS limit, the system will show the number of characters and message segments.

If your messages are consistently too long, it is better to switch to MMS messages. The format also allows you to enhance your messages with images, gifs, videos, PDFs, audio clips, and rich media. Plus, it gives you a 10x higher character limit (up to 1600) than SMS (160 characters).

There are several other advantages

  • Engaging content via MMS gets conversion rates as high as 70%.
  • MMS messages have a 20% higher opt-in rate than SMS. When you want to grow your text messaging list (or get more sign-ups for a campaign), sending an MMS would amp up your efforts.
  • MMS messages make your texts more interesting and 8X more likely to be shared. 

In closing, it is important to stress that Bulk SMS marketing in the United States is subject to various laws and regulations to protect consumers’ privacy and prevent unsolicited communications. Businesses engaging in bulk SMS marketing should familiarize themselves with these laws and regulations and ensure compliance to avoid legal liabilities. 

Bulk SMS laws include: 

Telephone Consumer Protection Act (TCPA): The TCPA regulates SMS messages and requires prior express written consent from recipients before sending messages via SMS. It also mandates opt-out mechanisms for recipients who no longer wish to receive notifications.

CAN-SPAM Act: While primarily focused on email marketing, the CAN-SPAM Act also applies to SMS. It requires that messages include clear identification of the sender, accurate header information, and opt-out mechanisms. Additionally, it prohibits deceptive practices in messages.

Federal Trade Commission (FTC) Guidelines: The FTC enforces various guidelines for SMS marketing. These guidelines encompass principles of truthfulness, accuracy, and fairness, as well as requirements for obtaining consent and providing opt-out options.

Further, several state-specific laws are involved as well. For example, California’s Consumer Privacy Act (CCPA) imposes additional requirements on businesses collecting and processing personal information of California residents, including provisions related to marketing communications.

Make sure you are always compliant during your bulk SMS campaign. CallHub always stays on top of the rules laid out by the Federal Communications Commission (FCC) and keeps the product up to date to ensure the highest level of compliance.

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