Posting this in case someone was in a similar situation as I was.
I returned to my country of nationality (Singapore) to apply for a visa that cannot be obtained in Taiwan (Bangladesh). In order to return to Taiwan while my Bangladesh visa was processed, I applied for a temporary travel document. Some countries would issue a passport with limited validity, a ‘temporary passport’, etc.
What your second travel document is called is irrelevant if you hold an ARC. However, it is important if you intend to enter without an ARC, which I will get to it later.
If you hold an ARC, according to the NIA service centre in Keelung who contacted the NIA at Taoyuan Airport, you cannot use the e-gates, or else the system will admit you based on your original passport and ARC, not the second travel document. Whether this actually matters in reality, I don’t know.
Another thing they told me is that you have to use the same travel document to enter and exit Taiwan.
On arrival at Taoyuan Airport (TPE) I went to the manual counters and they changed my passport number in the system for me. I was told not to change my ARC twice (on arrival at TPE and at Keelung NIA), since I intend to use my original passport on future entries.
This would work if the two travel documents have the same nationality and issuing state. Not sure if say, a dual national who attempts to enter with an ARC on a passport of a different country.
If you are a national of a visa-exempt country and intend to enter without an ARC with a second travel document, the following would matter, except US nationals who get visa-exempt access even on an emergency passport:
- If you get a second ‘full’ passport (it doesn’t say ‘temporary’ or ‘emergency’), you get the usual visa exemption.
- If your second passport is called a ‘temporary passport’ or ‘emergency passport’, you need to apply for a landing visa (essentially a visa on arrival) or a visa in advance.
- If your second document does is not called a ‘passport’ but a ‘travel document’, ‘certificate’, ‘document of identity’, etc., you need a visa in advance and cannot apply for a landing visa.
I confirmed this with the MOFA visa office at TPE in person, after showing her my temporary travel document from Singapore.