Best way to amend 2023 return

there really isn’t as you’d have to purchase the desktop version (which probably costs more than the tax itself) and then key in everything from the 2023 tax return so that an amendment can be determined. 

What is on Line 15 from your 2023 tax return and what is your filing status? While it’s great you want to be an upstanding citizen and pay the tax, it might be quite small and if the IRS hasn’t asked for it after this many years, it probably won’t. 

you could print out form 1040-X from the IRS website and do the amendment manually. 

I agree with NCperson in that the IRS probably won’t question your 2023 return at this point.

Regardless, you wouldn’t be able to upload or transfer your file from your professionally prepared return into TurboTax. You could use a desktop version of TurboTax, but you’d have to start from scratch.

More info on amending…..(Ideally you should go back to your accountant)

To amend a return you did somewhere else or you don't have the original .tax2023 data file,  you would first have to fill out Turbo Tax like you are doing the original return.  You have to recreate the actual wrong original return.  Then when it matches each line that you really filed you have to tell Turbo Tax you will mail it so it thinks it was filed.  Then you can amend it.

You would have to buy the prior year Desktop program here.  They only sell the last 3 years.  You need a full Windows or Mac computer to install it on
https://turbotax.intuit.com/personal-taxes/past-years-products