Before paying by check, make sure you’re not required to pay electronically. If you’re required to pay electronically and you instead pay by check, you’ll be charged penalties and interest. For details, see Electronic Payment Requirements for Businesses.
When paying by check, you must complete and enclose the correct payment voucher. Choose the correct voucher from the list below (depending on the type of payment):
Mail your check and payment voucher as directed in the instructions on the voucher.