Share article:

17 ways to collect your customers’ phone numbers for SMS marketing.

Last updated August 2023

There’s one thing getting in the way of success with SMS marketing. Numbers. We’re talking customer phone numbers, of course. 

Building a solid database of customer phone numbers is a critical step in any text-based marketing program. And the good news? It’s easier than you think. In this guide, you’ll find a huge range of tips and tactics for start collecting phone numbers.

Before you get started, keep these things in mind.

Know your audience: Aim for quality, not quantity.

There’s no point in collecting every phone number under the sun if the people behind those numbers don’t fall into your target demographic. Think about your ideal audience and hone your strategy accordingly. 

A good place to start is in looking at your existing customers. Get to know their needs and interests. For example, if you sell outdoor adventure gear online, then you’ll know your target audience is likely to be fit and healthy young adults who love a little adrenaline on their weekends.

Know the laws: Make sure you’ve got consent.

In many jurisdictions around the world, you need your customers’ consent to collect their number from you. In other words, you can’t just take their number from a form they’ve filled in on your website and use it to blast out promotional messages to them. Instead, you need to explicitly ask for permission. 

In the US, for example, some strict rules apply when sending text messages for business purposes. You can brush up on the basics of these opt-in and opt-out rules here. Make sure you understand the rules that apply in your area. If you’re unsure, consult a legal professional – and don’t forget, you can always contact our team with any questions.

Know the etiquette: Don’t spam people.

By sharing their cell number with you, your customers are putting their trust in you.  With this in mind, you must always:

  • Include options for customers to opt-out
  • Guarantee privacy of your customers’ details
  • Promise you won’t spam your customers – and stick to it
  • Make sure your SMS messages offer some value

One more thing. This probably goes without saying, but buying phone numbers is a bad idea. Even if a phone numbers list is legally obtained, sending messages to those numbers would be illegal without express consent.

Your SMS marketing will be far more effective if you’re texting people who actually want to be contacted anyway.

Want to try texting your database?


17 easy ways to collect your customers’ mobile numbers.

Now that you’ve wrapped your head around your target audience and the consent rules in your area, you’re ready to dive in and start building your database. Here are some great ways to rack up the numbers.

1. Text-in competitions.

Tempt your customers with a competition to win a cool prize. Remember, the numbers you collect are worth their weight in gold for SMS marketing, so make sure your prize is worth the exchange.

Text-in competitions are one of the easiest ways to collect phone numbers. You’ll just need a dedicated mobile number that customers can text their entries to. Here’s an example:


2. Keyword campaigns.

Similar to text-to-win competitions, keyword SMS campaigns are about giving your customers a great deal in exchange for their phone number. Run an ad asking them to text you, and you send them a special offer or discount in return. Using an dedicated SMS short code will make your number easy to remember, too. For example, ‘Text THIRSTY to 567411 for a free drink in-store.’

Woman on a laptop with SMS bubble examples floating around her.

3. Social media.

Use your social channels – like Twitter, LinkedIn, Facebook, Instagram, YouTube and TikTok – to connect with your potential customers.

To reach your target audience, you could run sponsored posts on your key channels, using strategies like competitions, keyword campaigns, live broadcasts, polls and stories to encourage followers to sign up to your contact list.

4. Make the exchange.

When you’re asking for something valuable like a customer’s phone number, you need to make it worth their while. What can you give your customers that no one else can?

A great example of a value exchange is when a B2B business offers an insightful eBook or report that helps prospective customers grow. By putting the asset behind a gated form, customers sign up and share their cell phone number. Too easy.

Brush up on text messaging trends.

Sinch MessageMedia Playbook Stack

5. Free trial or demo.

This is always a good one, particularly if you’re in the B2B space. When customers sign up, collect their mobile number using the online form on your website. If they’re signing up elsewhere, like at an event or through a shop window, ask them to send an SMS requesting the free trial or demo.

Want to try SMS?


6. Email.

If you’ve built up a solid database of email addresses for email marketing, use this channel to collect numbers. When you send your monthly newsletter or weekly promo email, encourage customers to reply with their cell phone number. You could sweeten the deal with an offer they can’t refuse. 

Don’t forget, if you already do email marketing, be sure to differentiate your SMS marketing. Customers won’t want to share their mobile number only to receive the same messages in both channels. Show them why they’ll want to subscribe – it could be something like first dibs on exclusive new lines, or Christmas sales, or a gift on their birthday.

7. VIP clubs.

Invite your customers to join a special VIP club by signing up with their cell number. Of course, you’ll need a VIP club in the first place – if you don’t have one, make sure that whatever you create offers tangible benefits, such as advance notice of sales and promotions, coupons, invites to exclusive webinars, and so on. It’s all about making sure your customers feel like they’re getting special treatment.

8. Partnerships.

Think of businesses who may complement your own, and consider joining forces to grow your databases. This can effectively double your marketing efforts and help you reach more potential customers.

9. Events and conferences.

If you’re participating in an industry event, make the most of the opportunity to collect attendees’ details. Use some of the strategies listed above – like competitions, giveaways or value exchanges – to encourage people to give you their numbers. Here’s what ours looks like:


10. Advertize your number.

Make sure your dedicated number is highly visible on all your advertising, from billboards to the side of your vehicle. On your ads, encourage customers to get in touch by using memorable keywords.

TOP TIP: Learn about the different kinds of SMS sender IDs to choose which is best for your business needs.

11. Website forms.

Add ‘phone number’ as a mandatory field on your web forms, from general contact forms to feedback forms and checkout pages in your online store. Don’t forget to include a checkbox if you need to comply with opt-in rules.

You could also use the form to capture customers’ preferences, by including a checklist of the products or services they’re interested in. Then, you’ll know more about what they want and can tailor your SMS marketing accordingly.

12. In-store campaigns.

To encourage customers to share their cell phone numbers when they’re visiting your store, think about what you could offer your customers.

For example, you could run a monthly prize draw asking people to drop their business cards in a bowl. Or, you could offer free samples, requiring customers to sign up with their mobile number.

13. Customer support calls.

If your business has a call center or takes support calls, your support agents could ask for phone numbers when new customers call in. On these calls, your team could encourage customers to sign up for SMS alerts – being sure to explain the benefits.

14. Chatbot.

If your site has a chatbot, use it to ask for customers’ phone numbers. Similar to customer feedback, make sure you include an automated form query that nudges customers to give you their mobile numbers. It’s not an unusual request – customers may want a reply from you later when they’re away from their computer. Learn about our Chatbox to SMS feature.

A laptop screen showing Chatbox to SMS popping up to talk to visitors

15. Call-to-actions.

Sign up forms, chatbots, social channels and emails aren’t the only places your brand can land a phone number. Don’t discount your Contact Us page.

Offer the option for people to get in touch via text message. It’s an easy, non-intrusive way for them to communicate with you – and you can collect their cell number while you’re at it.

16. Onboarding.

If you run a business where new customers need to sign up – whether you’re a salon that collects their details or you’re a software company – then use the onboarding stage as an opportunity to get their number, if you haven’t got it already.

17. Just ask.

Sometimes it just pays to ask. This is what one of our customers, confectionary specialist Lollyology, did when they were pivoting their business from bricks-and-mortar to online.

They needed customers’ numbers, so they simply asked everyone who walked through the door – adding a sweetener by reminding customers they’d receive extra discounts and promotions via text.

Most customers were happy to oblige, and they collected 200 customers’ numbers in just a few days. Read the case study.

Got your numbers?

Once you’ve built your database of phone numbers, it’s time to put your SMS marketing plan into action. Explore our messaging features you sign up for a free trial with Sinch MessageMedia.