South Korea eSIM for 7 days: Seoul and a second city

How much data 7 days in South Korea takes

One week in Korea: two cities and one transfer

A common seven-day shape is four nights in Seoul and three in Busan, riding the KTX from Seoul Station in a little over two hours. The other is four nights in Seoul and three on Jeju for nature. The first stays in big cities; the second turns into an island trip with a hire car or taxis.

Where data spikes and drops with a transfer

• Transfer day: timetable checks, in-app tickets and finding the platform, short but frequent bursts of data.
• On the KTX: music and video streaming can eat a lot, so download content before boarding.
• Busan days along Haeundae and Gamcheon: lots of photos and clips, balanced by café Wi-Fi.
• Jeju: driving between sights means continuous navigation, and signal can weaken in the hills, so download offline maps.

Which plan shape fits seven days

Seven days is the one length where our fixed Korea plans match the validity exactly, with 7-day plans of 1 GB and 500 MB, which suit people who rarely use data away from Wi-Fi. But the 8 GB normal estimate is far above 1 GB. For daily map users the 10 GB plan valid 30 days is more interesting, since the validity covers the whole trip and the spare allowance cushions transfer day.

Daily plans win when the two halves of the trip differ, say Seoul light on Wi-Fi and Busan heavy because you are out all day. But a daily plan locks one tier for every day, so for more flexibility a fixed plan that is big enough is often simpler.

Network and app notes for a two-city trip

• The Korea plans use SKTelecom / LG Uplus in both Seoul and Busan, so you do not switch plans when you move.
• KTX tickets are booked through the rail operator's app or site and may need identity checks; keep a screenshot in case signal drops.
• Use Naver Map or KakaoMap for city buses and Busan subway transfers.
• If you go to Jeju and hire a car, the rental firm sets licence and document requirements, so check with them directly.

A sample split of data across seven days

As a rough split, the first four days in Seoul run about 1 GB each with hotel Wi-Fi helping, transfer day about 1.5 GB for tickets, maps and music on the train, and the three Busan days about 1 GB each. That lands close to the 8 GB our estimate table shows. Seeing it day by day shows why a 1 GB plan for the whole week is gone by day two or three, and why a larger plan suits a two-city trip.

Bottom line for seven days

Our estimates are 4 GB light, 8 GB normal and 15 GB heavy. Two-city trips tend to push you past light because you depend on maps and mobile tickets. Cover the normal figure and download content before transfer day.