(CBS SF) — The Department of Motor Vehicles may owe thousands of Californians a refund after a state board says it overcharged residents for vehicle registration.

The California Board of Equalization claims the DMV is using drivers’ ZIP codes instead of their actual address to come up with the fees.

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According to CBS Sacramento, BOE member George Runner said he believes thousands of people have been overcharged, equating it to hundreds of thousands, if not millions of dollars.

The problem involves taxpayers who live in what’s called a split ZIP code.

Those include people who live in a city and people who live in unincorporated areas where the sales tax rate is different.

“You have some areas that have an 8 percent sales tax in the county and you have people in the city who have an 8.5 percent but they’re in the same ZIP code,” Runner said, who also claims the DMV refuses to use the Board’s look-up tool where it identifies rates by address.

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The DMV issued a statement saying, “The Board of Equalization uses tax rates based on ZIP code and directs DMV to do the same. As a member of the Board of Equalization,  Mr. Runner has the power to modify how tax rates are determined but has not done so.”

The DMV also released a letter to the BOE saying  it “will immediately begin exploring options for ensuring the correct assessment in those narrow circumstances where a split code may apply.”

The tax rate for a vehicle sale is based on the address of the registered owner, not where the sale takes place.

If you think you may be owned a refund, you can fill out a form at your local DMV office.

(California State Board of Equalization)

(California State Board of Equalization)

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