Can I cancel my education visa without traveling back to Bangkok?

Enjoy your whole day at immigration. I had to cancel my visa after my study and spent a whole day there waiting.

I had the same issue. Started school in Krabi, wanted to cancel the visa in Chiang Mai instead of travelling all the way back. People on the internet told me this was not possible. Well turns it was. I was relieved to be able to cancel it in Chiang Mai. Whether Phuket allows this I do not know but does not hurt to go in and ask

I have a similar problem: I'm on a 9-month ED visa, extended every 3 months. I've been offered a job outside of Thailand and will travel to take up that job very soon. But in case the job turns out to be a 'dud', I want to leave my ED visa status open (ie I will get a re-entry permit as I leave Thailand), so that I can return to continue my studies a week or so later. If the job is a good one, I may want to return back to Thailand at a later date, but not to continue on an ED visa - I'll apply for a DTV. But how can I cancel my ED visa if I've already left the country?

Unfortunately you will still need the cancellation letter, transcript, and letter to confirm that you have finished your course. These are the papers that I needed to submit after I cancel my ED plus visa for my Master education. And you will need to go to Immigration, get a queue from the N2 counter, and cancel it there. If you don’t get it cancelled, you will not be able to issue any new visa in Thailand.

I guess you're not on any visa at but an extension of stay, look in your passport. Extensions of stay can only be cancelled by the office that issued them. Leaving without cancelling an extension leaves it "open" in the immigration database, you would technically be on overstay and it can cause problems in future interactions with immigration offices