I have 2 passports - UK & Australia - for several years I've used only my UK passport in Thailand. It has a current Retirement ex + multi-re-entry stamp, so far this year I've used that passport twice for short trips to Thailand. But that passport is filling up fast. My Australian passport has never been used for Thailand and has heaps of pages left.

 

I have a flight from Perth to BKK next Tuesday, and a ticket back to Perth 21 days later. Is there any reason why I couldn't enter Thailand on my Aussie passport for this short trip? Getting 30 days visa free at Swampy, showing if asked a ticket out 21 days later, and a couple thousand bucks cash in AUD.

 

Also while in Thailand I might make a short (5-6 days) side trip to Cambodia, if so I'd be re-entering Thailand at a land border (Chong Chom).

 

So could I switch to my Aussie passport for this short trip to Thailand and Cambo and save a couple pages in my UK passport? Or would it be better to continue with my usual UK passport?

4 minutes ago, TSF said:

I have a flight from Perth to BKK next Tuesday, and a ticket back to Perth 21 days later. Is there any reason why I couldn't enter Thailand on my Aussie passport for this short trip? Getting 30 days visa free at Swampy, showing if asked a ticket out 21 days later, and a couple thousand bucks cash in AUD.

No problem. You can use either passport.

 

6 minutes ago, TSF said:

Also while in Thailand I might make a short (5-6 days) side trip to Cambodia, if so I'd be re-entering Thailand at a land border (Chong Chom).

 

So could I switch to my Aussie passport for this short trip to Thailand and Cambo and save a couple pages in my UK passport? Or would it be better to continue with my usual UK passport?

Yes. It really doesn’t matter which passport you use.

 

They will probably link your UK and AUS passports on their system. Dual nationality is very common these days. The fact that you used your UK passport before should have no bearing on future entries as an Aussie. But if the passports get linked the whole of your entry history will be available to the IO.

You should remember that your extension of stay(based on retirement) is linked to the UK passport - it is not possible to transfer that extension to the Australian passport. There is also the possibility of the passports being linked but whichever passport is used for entry must also be used to exit. It is not possible to swap passports at land crossings. 

1 hour ago, elviajero said:

No problem. You can use either passport.

 

Yes. It really doesn’t matter which passport you use.

 

They will probably link your UK and AUS passports on their system. Dual nationality is very common these days. The fact that you used your UK passport before should have no bearing on future entries as an Aussie. But if the passports get linked the whole of your entry history will be available to the IO.

Yes, that's not a problem for me, I'm not trying to hide anything, only save a couple of valuable pages in my UK passport, it's filling up fast and I'll need to renew it sometime soon but if I can stall it off for a while it'll suit me better.

1 hour ago, KarlS said:

You should remember that your extension of stay(based on retirement) is linked to the UK passport - it is not possible to transfer that extension to the Australian passport. There is also the possibility of the passports being linked but whichever passport is used for entry must also be used to exit. It is not possible to swap passports at land crossings. 

Yes, no intentions of switching passports mid-stream, I'd just like to enter Thailand with my Oz passport, get the 30 days stamp, and fly out on the same passport 21 days later. 

19 minutes ago, TSF said:

Yes, no intentions of switching passports mid-stream, I'd just like to enter Thailand with my Oz passport, get the 30 days stamp, and fly out on the same passport 21 days later. 

 

You may get the 3rd degree from the immigration chap if the system flags up your other passport "why you use two passports?".

 

Although you are doing nothing illegal these guys can get suspicious when they see something unusual going on.

 

2 hours ago, TSF said:

So could I switch to my Aussie passport for this short trip to Thailand and Cambo and save a couple pages in my UK passport? Or would it be better to continue with my usual UK passport?

Live a little.  Enter using your Australian, exit using same and then come back from Cambodia using your British passport.  Toss a coin!

6 hours ago, 4675636b596f75 said:

Live a little.  Enter using your Australian, exit using same and then come back from Cambodia using your British passport.  Toss a coin!

He was going to go to Cambodia by land, so that would not be possible.  When flying, you can switch (except Thailand -> Laos, where problems were reported doing this).

11 hours ago, Crossy said:

 

You may get the 3rd degree from the immigration chap if the system flags up your other passport "why you use two passports?".

 

Although you are doing nothing illegal these guys can get suspicious when they see something unusual going on.

 

Yes Crossy, that occurred to me and is the main reason why I made the post asking for advice/opinions. I don't want to get any hassle over this.

11 hours ago, 4675636b596f75 said:

Live a little.  Enter using your Australian, exit using same and then come back from Cambodia using your British passport.  Toss a coin!

Nah, can't do that, Thais need to see exit stamp from Cambo, or else they won't let you through, and vice versa. Anyway, even if I could do that it'd defeat the whole purpose...I want to use the Oz passport as much as possible as it hardly has a stamp in it (I use it for entry/exit Aust and they don't stamp) whereas the UK passport is filling fast.

All went well, no problems whatsoever, entered Thailand at Swampy last night, got 30 days stamp in my Aussie passport, if anything linked on the computer about me also having a UK passport then no mention was made of it.