Printed my taxes, have 2019 Forms 1040 ES payment vouchers for 2019. I am paying taxes on 2018 due to a 401withdrwl . Is this form for optional prepayment of 2019 taxes?

You are correct.  TurboTax prepares those vouchers as a "suggestion" for paying estimated 2019 taxes.  If you know you won't need to make estimated tax payments, you can ignore those vouchers.  See the TurboTax FAQ below for additional info.

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