How to Read ROC (Minguo) Dates on Any Taiwan Document

If a Taiwan document shows a date like 115/07/29, it is written in ROC (Minguo) years. Add 1911 to the first number to get the Western year: 115 + 1911 = 2026, so the full date is 29 July 2026. The month and day never change.

The one rule that reads every ROC date

Taiwan's official calendar counts years from 1912, the founding of the Republic of China, which is ROC year 1. Every date field on a government form, ID card or receipt that uses a small number for the year — instead of "2026" — is almost certainly using this system.

Formula	Western year = ROC year + 1911
Example	115/07/29 → 115 + 1911 = 2026 → 29 July 2026
Reverse	Western year − 1911 = ROC year  ·  2026 − 1911 = 115

Once you know the formula, you can read any ROC date in your head. For a full date with weekday and the formal written form, use the ROC year converter.

Spotting a ROC date at a glance

You don't need to know which document you're holding to recognise the format. Three signals give it away:

A year written as one to three digits, roughly 1–120, is a ROC year — no Western year in living memory is written that short. A four-digit year beginning 19 or 20 is a Western year. And Chinese-language fields marked 民國 (Minguo) or 中華民國 are explicitly ROC-dated; see every ROC date format for how these appear with slashes, dots and Chinese characters.

Where you'll meet ROC dates

Almost every official document issued in Taiwan uses this system somewhere on the page. The most common ones, with a page for each:

• National ID card — issue date and birth date fields
• ARC / residence permit — issue and expiry dates
• Driver's licence — expiry date on the card face
• NHI health insurance card — issue date
• Bank and insurance forms — date fields you fill in yourself
• Rental contracts — lease start and end dates
• Food and medicine packaging — printed expiry dates
• Birth certificates — date of birth and registration
• Marriage certificates — date of registration
• Government letters and official documents (公文)

Common misreadings

The most frequent error is treating a ROC year like a truncated Western year — reading 115 as "2015" because it looks like a short form of a familiar decade. It isn't: 115 is ROC 115, which is 2026. The gap between the misread year and the real one is always exactly eleven years, because that is the offset the whole system is built on.

A second trap is documents that mix systems: a residence permit issued in Taiwan uses ROC years throughout, except a birth date for someone born abroad, which may be printed in the Western year they gave. Read each field's label rather than assuming the whole document uses one system.

For the special case of years before the ROC calendar existed — written as 民國前 — see understanding pre-1912 ROC dates. For the two-digit rollover problem that hit systems when the ROC year passed 99, see the Y1C problem.

Why Taiwan still uses this system

The ROC calendar runs alongside the Gregorian calendar rather than replacing it, and both are legally valid in Taiwan. For the history and the practical reasons it has stuck around, see Minguo vs Gregorian.

Frequently asked questions

What is a ROC date and how do I convert it?

A ROC (Minguo) date counts years from 1912, the founding of the Republic of China. To convert one to a Western date, add 1911 to the year and leave the month and day unchanged. 115/07/29 becomes 29 July 2026.

How do I tell a ROC date apart from a Western date?

A year written as one to three digits between 1 and roughly 120 is almost always a ROC year. A four-digit year starting with 19 or 20 is a Western year. Context also helps: government forms, receipts and Taiwanese ID documents default to ROC years.

Which documents use ROC dates?

National ID cards, ARCs and other residence permits, driver's licences, NHI health insurance cards, household registration documents, bank and insurance forms, rental contracts, tax filings, birth and marriage certificates, court papers, and printed expiry dates on food and medicine.

Do months and days change in the ROC calendar?

No. The ROC calendar is the Gregorian calendar with a different year count. Months, days and weekdays are identical to the Western calendar, so only the year needs converting.

What is the most common mistake when reading a ROC date?

Reading a three-digit ROC year as if it were a shortened Western year — for example misreading 115 as 2015 instead of adding 1911 to get 2026. The two years are eleven years apart, which matters on expiry dates.