US retail major Walmart has committed to not using customers' personal data, income, shopping history or sense of urgency to determine what they pay.

In the letter, addressed to customers and members, president and CEO John Furner said using such information “to charge them more would violate the EDLP promise our business model is built on. We won't do it”.

EDLP refers to everyday low prices, the pricing principle the US retailer has followed for over 50 years.

Furner outlined three commitments.

The first is that prices will not vary according to who a shopper is or the time of day. He said income, shopping history, urgency or “what we think you could pay won't change the price”.

The second extends the same promise to Walmart's digital tools.

Information shared with Sparky, the company's artificial intelligence (AI) shopping assistant, or elsewhere will not be used to raise prices or conceal lower-priced options that meet a customer's needs.

Third, Walmart said it will keep using customer information “responsibly” and “respect” shoppers' choices.

Customers will decide whether to provide further details in return for more “personalised help”.

Furner said Walmart's staff will continue to oversee pricing and that the company will “monitor and test our technology against these commitments”.

“I've heard concerns about companies using that information and technology to charge you more,” Furner wrote. “I want to tell you where we stand: We price the product, not the person.”

The letter also covered the digital shelf labels being fitted in stores.

According to Furner, they help keep shelf prices in line with checkout prices and spare associates the task of swapping paper tags manually, freeing up time to assist customers.

On AI, Furner said the technology “rightfully also raises questions about the information it has access to”.

He described engagement with Sparky as “an invitation to serve you better, not to use your personal information to set a personalised price”.

He added: “We've never used the relationships our associates have with customers to charge more, and we won't do that with AI.”

Last week, Seattle became the first US city to prohibit grocery retailers from setting individualised prices for shoppers based on personal data.