Sim card with no expiry date

[Pagey]

I'm pretty sure this has been asked before but I can't find it and maybe things have changed over time.

I need a sim card that doesn't have an expiry date. The sim card will be loaded with 100 Baht but hopefully never used after initial testing and not need topping up.

With my AIS sim when I put 100 Baht on it gives an expiry date which is OK in my mobile as the expiry date is way in the future.

The sim will be in a car GPS tracker and will only be used if I ring the number, it then sends an SMS to my phone with it's GPS location, hence no need to top it up but needs to be current and active.

Any suggestions anyone ?

[georgy]

You can extend expiry by using an USSD code for a small fee which is deducted from your balance.

[Pagey]

Thanks Georgy.

I've now Googled USSD codes and found lots of info.

I found lots of info on this site about AIS, DTAC and True.

http://help.mobiletopup.com/knowledge-b ... of-my-sim/

True only costs 2 Baht per month to extend validity which is good to know.

I currently use AIS and according to this website no matter how much you top up you get 30 days credit so instead of topping up 100 Baht I can do 10 x 10 on my new sim to get 10 months validity.

[Big Boy]

I currently use AIS and according to this website no matter how much you top up you get 30 days credit so instead of topping up 100 Baht I can do 10 x 10 on my new sim to get 10 months validity.

Yes, I top the SIM card my tablet up similarly, then transfer the credit to my phone when it needs topping up.