The necessary Social Security numbers are accurate and included. No signatures are missing. You must sign your tax forms. Sometimes mistakes occur because directions for a form are misread or the instructions aren't followed. It's important that instructions are followed carefully for any forms filed.
Numbers are another source of common mistakes.
The arithmetic doesn't calculate, or the filer forgets to round up or down to whole dollar amounts, or the taxpayer combines payments. To avoid arithmetic problems, double check that you haven't transposed a figure. Remember that state tax forms are in whole amounts. So you round up to the next dollar if the amount is 50 cents or more, and you round down if it's less than 50 cents. Taxpayers must make separate payments.