Under certain circumstances, this payment voucher (Form 1040-V) may be submitted with your tax return. The IRS says that the use of this payment voucher will generally help save tax dollars because the IRS will be able to process payments more accurately and efficiently. In light of that fact, the IRS "strongly encourages" you to use the payment voucher if you qualify to do so, but the IRS does not require you to use the voucher.
Note: You may use the payment voucher only if:
You are filing Form 1040, Form 1040A, or 1040EZ, and
You have a balance due on your tax return.
You may not use the payment voucher if you are a permanent resident of Guam or the U.S. Virgin Islands.
The following lines will carry to Form 1040-V:
Form 1040, line 76
Form 1040A, line 48
Form 1040EZ, line 13