Is it a lot? It could be for a penalty. Did you have an underpayment penalty on 1040 line 38? It's very common and normal and expected for the IRS or state to bill you for more or send you a refund. You should bd getting a letter saying what the changed.
Generally, most taxpayers will avoid this penalty if they owe less than $1,000 in tax after subtracting their withholdings and credits, or if they paid at least 90% of the tax for the current year, or 100% of the tax shown on the return for the prior year, whichever is smaller.
