The giant office supply corporation Staples has again been found charging an online customer in Sandy Springs an incorrect, and higher, city of Atlanta sales tax. It’s an example of an issue that officials fear is contributing to lower-than-expected revenue from a transportation-oriented special local option sales tax in Fulton County.

Six months ago, a resident of Sandy Springs’ 30328 ZIP code – which is entirely within the city limits — complained about Staples’ promotional product subsidiary calculating the correct 7.75 percent sales tax on an online order estimate, but then incorrectly charging Atlanta’s 8.9 percent sales tax on the final order. After being contacted by the Reporter, Staples refunded the overcharge but declined to explain why the tax calculation was incorrect or whether it would be fixed.

In June, the same customer reported the same problem on a new order. Mark Cautela, director of corporate communications at the Massachusetts-based company, said the customer’s overcharge would again be refunded but again did not explain the error.

Sandy Springs leaders have a longstanding concern that ZIP code confusion is causing their sales tax collections to be misdirected to the city of Atlanta. The concern is based on businesses using software that report sales by ZIP codes. Many local ZIP codes use the preferred name “Atlanta” even when the addresses are actually in Sandy Springs.

John Ruch is an Atlanta-based journalist. Previously, he was Managing Editor of Reporter Newspapers.