Can I make a Federal tax payment before I file (I'm not quite ready to file but I know what I'll owe)? The estimated payment deadline has already past.

[josh-rotenberg]

I missed the deadline for the final estimated tax payment for 2018 (I made the others). I'm still working on my Schedule C inputs but in general I know (within a few hundred dollars) what I'll owe. Can I pay the higher amount now to the IRS and possibly get a refund if my final bill is slightly less? I should make the April 15th deadline but I'd like the peace of mind of knowing I'm paid in full before that.

[JulieR · Accepted solution]

Yes, you can make a payment towards your 2018 tax bill.  Go to https://www.irs.gov/payments to make the payment and designate the payment for "2018". Make sure to include that payment on your 1040, Schedule 5 "Other Payments and Refundable Credits", line 66.