A sales tax snafu at Walmart meant customers were charged twice

• Walmart accidentally taxed some Alabama customers twice after its system mixed up a tax change.
• Alabama's sales and use tax base rate on food was cut from 4% to 3% on Friday.

Walmart has begun issuing refunds after a mixup with sales taxes resulted in multiple customers being charged twice.

Alabama's sales and use tax base rate on food, which is added to varying local tax rates, was cut from 4% to 3% on Friday.

But instead of charging customers a new, lower rate of tax, several people got in touch with local media to say they had been charged twice.

Pictures of receipts sent to News 19 showed one Walmart customer had been charged a total of 17% in sales tax, instead of Walmart's new rate of 8% at that location.

The outlet said it confirmed the problem by purchasing an item at a local store.

Walmart did not immediately respond to a request for comment from Insider, which was made outside of normal working hours.

In a statement to NBC 15 News, Walmart confirmed that some of its customers and Sam's Club members had been charged two rates of tax.

"Our systems mistakenly charged both the old rate and the new rate at the time of sale. This issue has been fixed, and we could use your help informing some customers who may have been overcharged," Walmart said in the statement.

Customers are being encouraged to go to Walmart stores to receive a refund for the higher tax rate.

It's not the first time a sales tax change has caused havoc in Walmart stores.

In January, local media reported that Kansas shoppers were double-taxed after the state cut grocery taxes from 6.5% to 4%. Walmart said it resolved the issue and apologized for any inconvenience caused.