WASHINGTON, DC -- The extra money started coming last month, in our paycheck. Right around that time, the Internal Revenue Service rolled out a new tax table.

They use the tax table to figure out how much money you owe based on how much you make. And, with that new tax table taxpayers may be paying more money than they are supposed to be getting. So, when tax time rolls around next year, taxpayers may have to repay some of that money.

But, that doesn't necessarily mean taxpayers will have to write the IRS a check. Experts say you'll most likely just get a smaller refund come tax time.

The people who will make the biggest hit are married couples who both work, retirees who have income taxes withheld from their pension payments and people who draw social security but also have a job.

The IRS has created a calculator on its Web site to help taxpayers figure out how much money money taxpayers could end up owing. Click here.