Assuming it’s for a visit rather than permanent, you need a Visitor Visa. It’s not a complicated process but a bit lengthy. Go on the Immigration NZ website and you’ll be guided through. You have to be able to demonstrate, with evidence, your girlfriend’s ties to Thailand and that she will return to Thailand. I sponsored my wife for a visit (guaranteed all costs, committed to ensuring she would leave the country, provided my own bank statements), supported by land chanotes, details of family in Thailand, reference from work stating she was on vacation, and a cover letter from me outlining our relationship history. Visa approved in 3 days.
Yes you can, so long as you have the required funds in the bank. No requirement to seed the money for the change to Non-Immigrant O. TM 87 form to be completed, bank documents (bank letter, certified copy of bank statement, copy of passbook, balance in all 3 matching), map of where you’re living, then another photocopied set of the same documents. THB 2,000 for the change of visa exempt to Non-Imm O.
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