What are the requirements for filing a 90-day report on a Non-O visa in Thailand?

No... this Visa is valid 90 days and you have to leave Thailand. So no 90-day report.

If you ask for an EOS on this Visa, yes.... you have to submit a 90-day report.

You're only stamped in for 89 days, as the day you entered is counted as day one. So no.

Okay, lets sort this out, even if you totally forgot to do a 90 day report and ran past the 7 days you're allowed after the due date to file one, when you stamp OUT of thailand no one at passport control cares in the least if you EVER filed a 90 day report or not.

That is not their job, they just stamp people in/out of the country nothing else..

Also as

@Graham *****

correctly pointed out IF the O/P is in deed on a 90 day Non-O visa, they wouldn't have ANY 90 day report due because you can't stay in country long enough on that visa to actually have to file a report.

Your 90 day reporting starts once you apply for a year extension (not when you enter on a Non-O visa).

Be that as it may, even if the O/P is on a year extension they are leaving the country on/before their actual 90 day report is due and they will be fine stamping out without having filed one :)

No.

Ive overshot by 1 day on leaving.no repercussion from kap choeng (Surin prov) as i explained i overnight stay hotel Bangkok b4 fly back to Uk

If you are leaving Thailand - on that day

You can probably get away with not filing

Your 90 day check in .

When you are stamped back into Thailand , your 90 day check in will be 89 days from the date of your arrival stamp

No, on a Non-O Visa there is no 90 day report because you only get a 90 day stamp

No need to do a report. I accidentally went 91 days on my non O 90 day married to a Thai visa without any issues

IF you are in Thailand 90 days, you are required to file a 90 day report.