What are 2018 Form 1040 ES payment vouchers. This was not mentioned when we filed our 2018 return

[AndreaC1]

If you’re at risk for an underpayment penalty next year, the TurboTax software will automatically calculate quarterly estimated tax payments and prepare vouchers (Form 1040-ES) for you to print. More details are below.

Those print automatically depending on your tax situation and the information you entered on your return. If you don't need them, you can shred them. 

Why did 1040-ES estimated tax vouchers print out? Do I need them?

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