Do I need to go to tax court dispute over 2018 tax return whereas I forgot to list a nontaxable sale?

[cjphb1]

I sold personal residence and equity was less than 250k, so not taxable as it is within allowable deduction. my accountant sent amended return with cover letter.  have not heard back from them and it is more than 90 days

[DoninGA]

The amended tax return will take from 4 to 6 months or longer for the IRS to process.

Go to this IRS website for the status of an amended tax return - https://www.irs.gov/filing/wheres-my-amended-return

[Opus 17]

We don't know any more about your situation than what little you tell us, if you are working with an accountant, stick with them.

In general, if the IRS sends a letter proposing that you owe more tax for some reason, and you disagree, you would respond with a letter outlining your argument, and including any other proof or tax forms that support your argument.  If the IRS accepts your argument, they would send a letter saying the case is closed. If they reject your argument, they would send a letter denying your claim and re-stating the tax you owe.  That's the point where you would either appeal to their supervisor or take it to court.  

It sounds like you have sent your letter and are waiting for a response, so you just have to keep waiting.  The IRS is backlogged and not terribly competent even on a good day. 

[macuser_22]

Amended return typically take abut 4 months to process, but this is not a typical year - with COVID slowdowns and extra workload with stimulus checks, amended returns are taking  6 months or more to process this year.   Hopefully it was mailed certified or with another tracking service for proof that the IRS even received it.