For any foreigner staying in Korea more than about 90 days, one card effectively becomes the key to daily life — banks, phone plans, even hospitals ask for it. You must apply within 90 days of arrival. What is it?

The Alien Registration Card, recently renamed the Residence Card, functions as the foundational ID for any foreigner staying in Korea long-term, because so many everyday services — opening a bank account, signing a phone contract, registering with a hospital — require it as proof you're a properly registered resident. That's why the rule requires applying within roughly 90 days of arrival at the local immigration office, or via the government's HiKorea portal.

An International Driving Permit only covers driving privileges and expires quickly, and a T-money card is simply a transit payment card for buses and subways — neither serves as an identity document recognized by banks or government agencies.

Missing the 90-day window doesn't just delay convenience; it can actively block essential daily-life tasks, since so many Korean systems are built around checking this one card, making it worth prioritizing over almost anything else in the first months after arrival.