Yesterday I registered my prepaid TrueH Sim at KSK, and while there asked about extending validity. I plan to travel outside Thailand and wanted to make sure my number is still valid upon return but couldn't find much information in English online, at least for extensions beyond 60 days.

It's possible to extend by phone as long as a balance exists to cover cost. 3 baht for 30 days by dialing *934#

Don't know if there's a maximum but, within the past 24 hours, I've extended for an additional 120 days.

Maybe this information has been in one of the frequent SMS messages I've received but since they're in Thai I can't read them. I've tried to change languages at the True shop in KSK several times but have been told 100% of text messages can't be solely in English. Seems 95% are still in Thai but I've finally given up trying to switch.

With Truemove H - Every time you top up you get an additional 30 days validity... You can top up multiple times and accumulate up to 365 days of validity...

The easiest way to do this to to go to your nearest 7-11... Outside you will see a small ATM like machine (Usually it is orange)... these are Top-Up machines... You can top 10 baht (Plus 3 baht fee - so have 13baht with you)... For each time you do this you accumulate 30 days to the max of 365... (You should get a text overtime you do this notifying you of your balance and validity date)... Also if you have online banking you can do the same thing without 3 baht fee but the minimum toupee is 50 baht...

Yes, I know about the orange machines and have spent much time staring dumbly at them, unable to figure out what to do. Dialing *934# is much easier for my feeble brain.

The screen is touch sensitive... There is an option to change the menu to English... After that pretty straight forward ;-)

Why not go into the 7/11 and top-up inside? Why bother with the orange machine? Give the clerk 50/100 baht, enter your phone # on the keypad, and bingo. Moments later you will get a series of text messages informing you of the results.

Why not go into the 7/11 and top-up inside? Why bother with the orange machine? Give the clerk 50/100 baht, enter your phone # on the keypad, and bingo. Moments later you will get a series of text messages informing you of the results.

Because the traditional top-up cards/online banking or online phone topups will only give you 30-60 days MAXIMUM validity capped from the date you topup, regardless of how many times you do it or amount of topup.

Now the orange machines (usually outside 7-eleven or established convenience stores) allow topups as low as 10 baht each, with 2 baht fee. These topups allow you to extend the validity in 30 day increments up to 1 year (365 days from topup date).

AIS and TRUE topup machines can have denominations as low as 20 baht; not sure if you can bypass the 60 day max validity cap with these topups.

True seems to have added an option to get 365 days vs 60 day max validity by using *934# .

Why not go into the 7/11 and top-up inside? Why bother with the orange machine? Give the clerk 50/100 baht, enter your phone # on the keypad, and bingo. Moments later you will get a series of text messages informing you of the results.

Because if you want to add say 6 months validity you will need to ask the nice lady behind the counter to do a 50 baht charge SIX times... This is a lot of work for her for something that requires no straws or a sack... You will get standard F$&k you smile about the third one in...