After you file

Those 1040ES vouchers automatically print out when you print your Form 1040. If you are just now getting ready to file your 2018 tax return, then disregard them unless you want to make an estimated payment for 2019 taxes. They are not for 2018 tax due. You are obviously too late to use those vouchers to make the quarterly payments toward 2019 tax--which is what they are for. They are not mandatory--they are optional to use if you wanted to make four equally spaced out payments toward your 2019 taxes. You have until October 15, 2019 to e-file your 2018 tax return. After that, e-filing for 2018 will be shutting down, and a 2018 return will have to be printed, signed and mailed instead. The online software will also be shutting down, so if you are not finished preparing your 2018 return by then, you will have to download desktop software to a full PC or Mac to finish the return.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**