Just as with emailing, regular verification and cleaning of your phone contact lists are crucial for the success of your SMS marketing campaigns. This can be managed directly within your company, internally, or by using a specialized platform. In this article, we suggest 6 best practices that will help you maintain the quality of your databases and thereby ensure better results when sending your messages.

1) Perform an initial verification during data entry

When a customer or prospect provides their contact information, consider verifying the phone number provided right away. This will allow you to immediately see if there are any errors, rather than accumulating entries and eventually ending up with a list containing several contacts with incorrect numbers.

2) Regularly check your contact lists

People often change their phone numbers. It is therefore important to regularly update your databases by verifying that the numbers listed are still valid. This will prevent you from sending SMS messages that will not reach their intended recipients.
Here, the use of an API will be invaluable, as it will allow you to perform these checks without having to contact each individual to verify their number.

The frequency of cleaning varies according to usage. It can range from once a month to once a quarter, with some companies choosing to do it only once a year.

3) Avoid purchasing or renting phone databases

We can’t emphasize this enough, it’s more than advisable not to buy or rent pre-made contact lists. While it may be more convenient and quicker than building a list organically, you risk ending up with a high percentage of incorrect numbers or, worse, contacts who have not consented to receive messages from you.

4) Clean your contact list

When you encounter incorrect phone numbers, incomplete, duplicated, poorly formatted, or no longer active, you can choose to edit them (unless they no longer exist), or decide to delete them. This cleaning is essential to keep a clean, reliable, and qualitative database, which you rely on for your SMS marketing campaigns. Specialized platforms like Captain Verify can detect these different types of invalid phone numbers, correct them, and delete them. They provide a significant time-saving advantage, as this is a lengthy and tedious task.

5) Normalize the format of entered numbers

When you enter new phone numbers, we strongly advise you to use a specific formatting. For this, use the E.164 standard (international public telecommunications numbering plan) which will allow you to obtain a base standard for all the phone numbers on your list, and avoid potential duplicates or data entry errors.

6) Know the type of phone numbers listed in your list

There are several types of phone numbers. Between mobiles, landlines, or premium-rate numbers, it’s not always easy to keep track. However, when you call or write to a contact, it’s important to know what type of number it is. A business call will generally be less well received if it’s made to a contact’s landline at home, rather than their business phone. Similarly, sending an SMS to a landline would be completely pointless.

In conclusion, it’s imperative to regularly verify the phone numbers listed in your database. This verification can be done at the time of collection, but it must also continue over time by performing regular cleanings. In this way, you will ensure high-quality contact lists and improved performance in your marketing campaigns.



I bring my expertise in digital marketing through my articles. My goal is to help professionals improve their online marketing strategy by sharing practical tips and relevant advice. My articles are written clearly, precisely and easy to follow, whether you are a novice or expert in the matter.