See below as to where you enter the payment information. And, yes, your January 2019 voucher is for 2018.
If you made estimated tax payments in 2018 towards your federal, state, or local taxes, enter them in the Estimated and Other Income Taxes Paid section.
- Search for the term estimated tax payments
- Select the Jump to link.
- Choose Start next to the type of estimated tax payment you'd like to enter.
- Enter the amount of estimated tax you paid at each of the quarterly due dates.
