台灣 · 統一編號
Taiwan UBN Checker
Check a Taiwan Unified Business Number (統一編號) for format and check digit, and look the company up in the Ministry of Economic Affairs register.
What is a Taiwan Unified Business Number?
A Unified Business Number (統一編號, UBN) is the 8-digit number that identifies a business — or a withholding agent — in Taiwan’s tax and company registers, printed on its uniform invoices. Its last digit makes the weighted total divisible by 5 — for example 97179430 for Far EasTone Telecommunications.
Taiwan UBN format
Eight digits checked with the weights 1-2-1-2-1-2-4-1.
(total ÷ 5)
Example: 97179430 (遠傳電信 Far EasTone Telecommunications Co., Ltd.).
- 8 digits: Numbers only, no prefix; leading zeros are part of the UBN.
- New rule: Since the 2023 change the weighted total must be divisible by 5 (previously 10). The sample 12345678 fails both.
- Companies only: The lookup covers companies in the MOEA register; sole proprietorships and branches are not found.
How to check a Taiwan UBN
- 1 Find the 統一編號 on the seller’s uniform invoice or website.
- 2 Enter the 8 digits above. The checker validates the format and looks the company up in the MOEA register.
- 3 If a recent UBN is shown as invalid, check it on the Ministry of Finance’s tax-registration search instead.
- 4 Find links to official lookups in our official database guide.
Frequently Asked Questions
How many digits is a UBN, and what does it look like?
Eight digits, numbers only, with no prefix — for example 97179430 for Far EasTone Telecommunications. Keep any leading zeros.
How is the UBN check digit calculated?
Multiply the eight digits by 1, 2, 1, 2, 1, 2, 4 and 1, add the digits of each product, then add up the results. The total must be divisible by 5. If the seventh digit is 7, that position can count as either 1 or 0.
Why does a valid new UBN fail some validators?
Taiwan’s Ministry of Finance relaxed the rule from “divisible by 10” to “divisible by 5”, asked systems to update by 31 March 2023, and began issuing such numbers as the old ones ran out — about 70% of businesses registered since 2024 have one. Validators still on the old rule wrongly reject them; ours applies the new rule.
How do I look up a company by its UBN?
The Ministry of Economic Affairs’ company search shows the registered name, status and address of companies. For sole proprietorships, branches and tax status, use the Ministry of Finance’s tax-registration search.
Must a B2B invoice show the buyer’s UBN?
Yes. A triplicate uniform invoice issued to a business must state the buyer’s name and UBN.
Is the UBN the same as the personal ID number?
No. A Taiwanese personal ID number is a letter followed by 9 digits. The UBN is the 8-digit number of a business or a withholding agent.
Last reviewed: , against official sources.
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