I've already paid my first 2 quarterly Estimated payments and am trying to pay the last two today...but IRS direct does not give me the option for tax year 2024. Does this mean I cannot pay the last 2 payments?
no you can't. at least not electronically or online.
you could print and mail a 2024 1040-ES with the amount reflecting both quarters.
another method would be to pay using the 2024 extension option.
your payments are late so depending on your tax situation there could be underpayment penalties.
The deadline for making 2024 estimated payments was Jan 15 2025.Any payments made now would be for this year 2025.
2024 is over. I would enter them on the IRS Direct Pay as 2024 Balance Due payments. You don’t enter them into your return but just mentally subtract them from the tax due on your return. So on your return say you will mail a check which you don’t need to mail since you already paid Online. Unless you still owe some more.