Countries That Use the MM/DD/YYYY Date Format (Middle-Endian)

When an American writes 12/31/2025, they mean 31 December — MM/DD/YYYY, month first. This is the middle-endian order, and while far fewer countries use it than day-first, it dominates one of the world's largest markets, so you meet it constantly online.

What "middle-endian" means

The date starts with the month (the middle-sized unit), then the day, then the year: 12/31/2025, 12-31-2025 or 12.31.2025. It reads the way Americans say it — "December 31st, 2025."

Why it causes confusion

03/04/2025 is 4 March in the United States but 3 April almost everywhere else. If you book travel, sign a contract or fill a form across borders, this one difference can be expensive. The safe habit: write the month as a word, or switch to YYYY-MM-DD. To count the gap between two dates whatever the format, use the Date Difference Calculator.

Countries that use MM/DD/YYYY

The month-first order is primarily used in the United States and its territories, with a handful of other countries using it in some contexts:

United States of America, American Samoa, Guam, Puerto Rico, U.S. Virgin Islands, U.S. Minor Outlying Islands, Northern Mariana Islands, Marshall Islands, Micronesia, Palau, and — in some contexts — Canada, the Philippines, Kenya, Ghana, Nigeria and a few others.

Outside the US and its territories, most of these countries use MM/DD/YYYY only in specific settings and use day-first order elsewhere.

Frequently asked questions

Which country uses month first?

The United States is the main country that writes dates month-first (MM/DD/YYYY), along with its territories.

Why does the US use MM/DD/YYYY?

It mirrors the spoken American style ("December 31st"). It became the written standard there, even though most of the world writes the day first.

What is the safest date format for international use?

YYYY-MM-DD (ISO 8601). It is unambiguous and sorts correctly, which is why computers and standards bodies prefer it.