The visa-free entrance to Jeju does not apply to citizens of 24 countries/regions and 10 other countries.
From June 1, 2022, travellers are allowed to enter Jeju and Yangyang visa-free via international airports. The visa-waiver program, which allows international travellers to visit Korea short-term without the requirement of a visa, was suspended on June 1, 2020, as a precautionary measure against COVID-19.
Although most international travellers will be allowed to enter Jeju Island visa-free, exceptions apply. The visa-free entrance to Jeju does not apply to citizens of 24 countries/regions* and 10 other countries** that have mutually suspended the visa-waiver program with Korea (Japan, Hong Kong, Taiwan, Macau, etc.).
As for Yangyang, only groups of 5 or more travellers from Vietnam, the Philippines, Indonesia, and Mongolia (effective October) can enter visa-free. To be waived of visa requirement, the group of tourists must travel to Korea through a designated travel agency.
* Countries/regions that require a visa to enter Jeju International Airport: Iran, Sudan, Syria, Macedonia, Cuba, Kosovo, Palestine, Afghanistan, Iraq, Ghana, Nigeria, Yemen, Egypt, Gambia, Senegal, Bangladesh, Kyrgyzstan, Pakistan, Somalia, Uzbekistan, Nepal, Cameroon, Sri Lanka, Myanmar
** Subject to change; for further details on visa eligibility, please check with the embassy or consular offices of your country in Korea.