This is going to be complicated and highly critical of Nok Air. If that bothers you, then maybe you ought not read this.
Nok Air recently offered what they call "Gift Vouchers" worth 500 baht toward the payment of airfare for 350 baht each. Great. Save 150 baht.
There are some caveats. You can only use one voucher per booking. If you use a voucher, the only payment option is via credit card.
We tried to book a round trip for two from Don Mueang to Hat Yai. The fare was 1579 each for the outbound trip and 1679 each for the return trip for a total of 6516 baht. The fee for paying by credit card is 128.40 baht per person per flight for a total of 513.60 baht. The total price was 6529.60 baht (after applying the 500 baht voucher) plus the 350 baht I paid for the voucher for a total of 6879.60 baht. (Let me know if my math is wrong here.)
Booking the ticket without the voucher cost the total airfare of 6516 baht plus a 64.20 baht fee for paying by QR code which, I believe, is the cheapest option. The total was 6580.20.
In other words, using the voucher costs a net of 299.40 baht more than not using the voucher.
The credit card processing fee (around 8% in this case) seems excessive as does the requirement that you have to pay by credit card if you use a voucher.
According to the voucher terms of service, it is refundable once the voucher travel period has expired. I guess that's the only reasonable option.
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