What should I know about border bouncing from Thailand to Singapore if I've overstayed by one day?

Go to imigration ask for extension

@Elise ********

you might be better off just bouncing out and back by LAND with a service that takes foreigners to the border

US passport is allowed TWO 30 day free entry by land in a calendar year

and

you won't get hassled about why you're "living here" on free stamp entries like can happen when you fly in especially if you do one of those "stay out just a few days" bounces.

You're not fooling the officers at passport control in the least 😮 and they know the only reason you left was to come back on a new free entry stamp 😕

I'd say if all you're wanting is a new free 30 day stamp, bounce with a service by land to get it

@Elise ********

what is your nationality? Your profile seems to show you're Russian.

Just flown this route with Scoot, stayed 3 hours in Singapore. Though I do have a Non O visa.

Overstay should not cause a problem. It’s only when you get picked up by police that they can then deport you.

As for coming back next day, that is down the IO. If he thinks you are living here and border bouncing to stay here, eventually they will ask questions

If overstay is less than 24 hours and flying out the fine will be waived and you'll get a stamp stating as such.

Probably all depends on your stay history in Thailand.