Mainland settles taxes in March–June but Taiwan files in May — how do I claim the credit in time?
This timing mismatch is the single most annoying part of cross-strait tax compliance. Taiwan's filing season (May 1–31) closes before mainland China's annual settlement (March 1–June 30) produces your final tax certificate. The practical answer: file Taiwan on time with your best estimate of the credit, then file an amended return (更正申报) once the mainland numbers are final.
The two calendars
| Jurisdiction | Filing season | What's final when |
|---|---|---|
| Taiwan | May 1–31 | Prior calendar year's income |
| Mainland China | March 1–June 30 | Prior calendar year's settlement; final tax known only after you settle |
If your mainland settlement isn't done by May, you can't have the final payment certificate in hand for the Taiwan filing.
The standard workaround
- File Taiwan on schedule (never miss May 31 — late filing penalties are worse than an imperfect credit claim).
- Claim the credit on your best available figure — withholding certificates and pay records you already have.
- Complete the mainland settlement, get the final 完税证明, run it through SEF verification.
- File an amended Taiwan return with the final numbers and the verified certificate.
What not to do
Don't skip the Taiwan filing to "wait for the mainland paperwork" — the late-filing penalty and interest will cost more than the timing inconvenience. And don't invent a mainland tax figure for the May filing; use documented withholding amounts and label estimates as estimates.
A concrete timeline
Take tax year 2025 as an example:
| Date | Action |
|---|---|
| May 1–31, 2026 | File Taiwan return on time; claim credit on documented withholding |
| Mar 1 – Jun 30, 2026 | Complete mainland settlement; obtain final 完税证明 |
| June – July 2026 | SEF verification of the certificate |
| After verification | File amended Taiwan return with final figures |
The overlap is tight but workable — the key discipline is never letting the Taiwan deadline slip while waiting on mainland paperwork.
Frequently asked questions
Can I get a filing extension in Taiwan?
Extensions exist but are limited; the standard advice is to file on time and amend. Confirm current extension rules with your CPA.
Does the amended return reopen everything?
An amendment draws attention to the return, so make sure the rest of it is clean. Keep all supporting documents for both jurisdictions together.
What if the final mainland tax is lower than my estimate?
Then your Taiwan credit shrinks and you may owe a small balance on amendment — plus modest interest. Still far cheaper than missing the deadline.
Sources
- https://www.ey.com/zh_tw/newsroom/2026/03/ey-taiwan-news-release-2026-03-18
- Taiwan Income Tax Act — filing and amendment provisions; PRC IIT annual settlement timetable