It may seem like a simple question at checkout: **“Do you have a phone number with us?”** Many shoppers answer without thinking, assuming it’s only needed for loyalty rewards or discounts. In reality, that number can become a key part of your customer profile, linking your purchases over time and giving retailers a clearer picture of your shopping habits.

By using your phone number, stores can track what you buy, how often you shop, which promotions you respond to, and even seasonal spending trends. This information helps businesses improve inventory, personalize offers, and recommend products. In some cases, purchase history may also be combined with data from loyalty programs, websites, or mobile apps, depending on the company’s privacy policy and your choices.

That’s one reason you may notice ads for products you recently purchased. While companies are generally required to explain how customer data is used, **“the amount of data collected may surprise many shoppers.”** Some information may also be shared with service providers or marketing partners, making it important to understand how your data is handled.

There is also a security concern. Any time personal information is stored, there is a risk of exposure if a company experiences a data breach. Although businesses invest heavily in cybersecurity, no system is completely protected. Sharing less personal information when it isn’t necessary can reduce your digital footprint and limit potential risks.

The good news is that giving your phone number is often optional. You can decline, ask about other ways to receive discounts, or review the retailer’s privacy policy before deciding. Understanding the trade-off between convenience and privacy helps you make informed choices and better protect your personal information while still enjoying the benefits that matter most.