Where to enter the credit card tax payment fees?

[r_1]

As per the IRS, the credit card "convenience" fees charged for making tax payments are deductible.

See the formal determination here: https://www.irs.gov/pub/lanoa/pmta2009-002.pdf
And the relevant law here: https://www.law.cornell.edu/uscode/text/26/212

However, there is no clear area in TurboTax 2021 where to enter this "ordinary and necessary expense under section 212(3) of the Internal Revenue Code."

Where is one supposed to enter this expense, to ensure it gets deducted properly as a necessary expense? (Which presumably means it still gets deducted even with the standard deduction vs. itemized.)

[Bsch4477]

If you are a business deduct as an expense on your Sch C. 

If you are an employee you can’t deduct that expense since miscellaneous expenses can no longer be deducted after 2018. 

[rjs]

You cannot deduct the credit card fees for tax payments. That's why there's no place to enter it in TurboTax.

The Chief Counsel Memorandum that you referenced is from 2009. It is no longer applicable. A lot has changed in the last 13 years.

The deduction for credit card fees is an itemized deduction. IRC section 212 is under Part VII, which is "Additional Itemized Deductions for Individuals." Furthermore, the tax reform law that was passed in 2017 contains "Sec. 11045. Suspension of Miscellaneous Itemized Deductions." That section of the law added the following to IRC section 67.

"(g) Suspension for taxable years 2018 through 2025
Notwithstanding subsection (a), no miscellaneous itemized deduction shall be allowed for any taxable year beginning after December 31, 2017, and before January 1, 2026."

So while the text of the provision remains in the Internal Revenue Code, it is suspended for 2018 through 2025.

Even when you could claim the deduction, prior to 2018, it could only be claimed as an itemized deduction. It could not be claimed as a separate deduction if you took the standard deduction.

IRS Publication 529, Miscellaneous Deductions, page 4, says "The convenience fee charged by the card processor for paying your income tax (including estimated tax payments) by credit or debit card is a miscellaneous itemized deduction and is no longer deductible."