Do you need to go to the immigration office to report after renewing a 12-month visa in Thailand, or can it be done online?

Ask them to reset it when you pick up your extension. That's it done for the first time, then you can do it online thereafter.

You can do it online, in theory. Some people say the online system always works for them, others say it never works. I always try online, but I leave enough time to have my agent do it in person when it rejects me or just never responds at all, which is what happens 75-80% of the time.

Get agent to do it ! 100 b or yes you can do online !

Steve Hemming . . well, if you do the financial proof using the 800,000 THB bank deposit as proof, some Immigrations will put a note into your passport, asking you to re-visit them three months after you got issued the new 1-year extension of the stay permit, with an updated bankbook to show your deposit didn't fall under 800,000 THB within these 3 months. And you would be automatically doing your 90 days report during that visit. If there is no such note, well, and if they have NOT clipped a new 90-days due date slip into your passport, your 90-days report remains due 90 days after your entry (if you entered). Otherwise if they clipped the next due-date slip into your passport when you got issued the new 1-year extension, they would have recognized your visit on Immigration as being a valid 90-days report

You are not able to renew a visa at your immigration office, what are you talking about?

No, only the first 90-day-report has to be done in person, after that you can do it online (if it works …).

Ask when you do your extension

I'm sure the IO will know

You don't have a visa and your not renewing anything. You have an extension of stay and it requires a new application every year. Saying that you should be able to do your 90 days report online