Choosing a plan
Japan & Korea: One eSIM or Two?
Updated 27 September 2026
Japan and Korea are one of the most popular combined trips out of New Zealand - a short hop apart, both easy to fly into direct or via a stopover, and different enough to justify splitting a holiday between them. The one thing that trips people up before they've even left home is the phone plan: is it a single eSIM covering both countries, or a Japan eSIM and a Korea eSIM you install and switch between?
There's no single right answer - it depends on how long you're spending in each country and whether you'd rather juggle two eSIMs or pay a bit more for one that just works everywhere. This guide covers the trade-offs, then runs the numbers on today's prices so you can see which setup actually costs less for your trip.
How most Kiwis do a Japan and Korea trip
Tokyo or Osaka to Seoul is a short flight - a couple of hours rather than a long-haul leg - so it's an easy add-on rather than a second trip in its own right. Most travellers do one country then the other rather than bouncing back and forth, commonly landing in Japan first and finishing in Korea (or the reverse), with the split of days depending on which country's the main focus.
How long you spend matters more than anything else here. A first combined trip is often 10-14 days total, enough for Tokyo or Osaka plus Kyoto on the Japan side and Seoul plus a day trip on the Korea side without feeling rushed. Three weeks lets you slow down and add a second city or region in each country - Hokkaido or Kyushu in Japan, Busan or Jeonju in Korea.
One eSIM for both countries, or two separate ones?
A single regional eSIM covering both Japan and Korea means one QR code, one install, and nothing to think about at the border - genuinely appealing if you'd rather not touch your phone settings mid-trip. The trade-off is that a bundle splits its data and validity across two countries instead of dedicating a full plan to each, so if one leg of the trip is much longer or heavier on data than the other, it can work out less efficient than sizing each country separately.
Two country-specific eSIMs - one for Japan, one for South Korea - let you size each leg exactly to how long you're there and how you'll use your phone in it, at the cost of one extra install partway through the trip. Neither approach is wrong; it comes down to how much that one extra step is worth to you, and how the numbers stack up for your actual trip length. See the comparison below for today's prices both ways.
Switching between eSIMs when you cross the border
If you go the two-eSIM route, install both before you fly, while you're on home wifi - there's no need to wait until you land. Keep your original eSIM installed rather than deleting it once you've landed in the second country; you can always reinstall or reactivate a data-only eSIM, but it's one less thing to deal with if you don't have to. When it's time to switch, just set your phone's mobile data line to the new eSIM and turn data roaming off (or leave the old eSIM's data line switched off) for the one you've finished with.
The whole process takes under a minute in your phone's settings and doesn't need you to find a SIM tool, a signal, or a shop counter - which is the main advantage of doing it this way over hunting for a local SIM in each country.
How much data you'll need across both countries
Both legs of this trip lean on your phone more than a typical beach holiday - constant map use getting around Tokyo's or Seoul's train and subway networks, translation apps for menus and signage, and photos everywhere you turn. As a rough guide, light use (maps and messaging only) runs about 1-3GB a week per country, regular use with some streaming and video calls home sits around 5-10GB a week, and heavy daily streaming or hotspotting a laptop for work pushes toward 15-20GB+ a week - see how much data you actually need for the full breakdown by activity.
Size each leg to the days you're actually spending there rather than splitting your total trip data evenly - a long weekend in Seoul tacked onto ten days in Japan needs a lot less data than the reverse.
Coverage in Japan and Korea
Both countries are well covered in the places most travellers spend their time - city centres, train lines and major tourist areas in Tokyo, Osaka, Kyoto, Seoul and Busan all have strong, reliable signal. Coverage thins out the way it does anywhere once you're well outside the cities - deep in the mountains, on some smaller islands, or in national parks - so it's worth downloading offline maps for any serious hiking days on either leg, the same as you would at home.
Current pricing for Japan and Korea eSIMs
Japan eSIM plans currently start from $4.99 and South Korea eSIM plans start from $4.99, with larger sizes and longer validity windows available on both - see the full, current line-ups on the Japan eSIM plans and South Korea eSIM plans pages. Prices update daily, so what you see there (and in the comparison below) is always current.
Setting it up before you fly
However you split it, install everything on wifi before you leave home so it's just a matter of switching a toggle once you land - see the setup guide for the two-minute version. If you're going the two-eSIM route, it's worth labelling each eSIM with the country name in your phone's settings while you're setting up, so there's no guessing which one to switch on partway through the trip.
One eSIM or 2 separate plans? The numbers
Here's a typical two-week Japan and Korea trip, split evenly across both countries, priced both ways with today's plans.
Here's a 14-day trip split evenly across 2 countries (about 7 days each), sized for regular use, priced from today's plans:
| Option | Plan | Price |
|---|---|---|
| Japan | 5 GB, 30 days | $9.99 |
| South Korea | 5 GB, 30 days | $9.99 |
| 2 separate plans | $19.98 | |
| Asia · 14 countries | 10 GB, 30 days | $27.99 |
On today's prices, separate plans work out $8.01 cheaper - worth it if you don't mind juggling 2 eSIMs. If you'd rather not, one Asia · 14 countries eSIM covers the lot. Prices update daily, so the comparison always reflects what you'd pay today.
Other bundles and single-country plans
If you're visiting more than one of these places, a regional bundle means one eSIM for the whole trip - no new QR code at each border. If you're mostly in one country, its own plan is usually cheaper. Current options:
- Asia · 14 countries - covers all 2 of the places in this guide, from $8.99
- Asia · 20 countries - covers all 2 of the places in this guide, from $9.99
- Japan & South Korea - covers all 2 of the places in this guide, from $10.99
Single-country plans
Things to know before you go to Japan and Korea
- Check when the plan actually starts - Look at the "About this eSIM" panel on each plans page before you buy - most plans start the first time your phone connects to a network in that country, so it's fine to buy both well ahead of your trip. A handful start the moment you install the profile instead, so for those, install right before you fly rather than weeks out.
- Hotspotting works on both - Hotspot/tethering is included on eSIM plans for both countries, so you can share your connection with a laptop or another device. It counts against your data allowance like any other use, so factor it into the sizing above if you're planning to work from a laptop on either leg.
- Your phone needs to support eSIM and be unlocked - Most phones sold in NZ from the last few years support eSIM, but it's worth double-checking your specific model and that it's carrier-unlocked before you rely on it for either country - see the setup guide for how to check.
- Free wifi isn't as reliable as it sounds - Free Wi-Fi is common in airports, stations and cafes in both countries, but it often needs a sign-up or an app, drops out as you move between hotspots, and gets scarce outside the cities. Treat it as a backup rather than something to navigate by - have your eSIM doing the work instead.
Japan and Korea FAQs
Is one eSIM enough for a Japan and Korea trip?
It can be - a single regional eSIM covering both countries exists and works for plenty of travellers, particularly on a shorter trip where the convenience of one install outweighs sizing each country separately. If your trip is lopsided (say, ten days in Japan and three in Korea) or you want to size data exactly to how long you're in each place, two country-specific eSIMs usually make more sense. Run both totals through the comparison above for your own trip length.
How many days should I spend in Japan and Korea?
Most first-time combined trips run 10-14 days, enough for a couple of Japanese cities plus Seoul without feeling rushed. Three weeks lets you slow the pace and add a second region in each country, while a week or less usually means picking one country as the main focus and treating the other as a short add-on.
Do I need to remove the Japan eSIM before installing the Korea one?
No - install both before you fly and just switch which one is set as your active mobile data line when you land in each country. There's no need to delete or reinstall anything mid-trip; leaving the eSIM you've finished with installed (just switched off) is simpler than removing and re-adding it.
Does hotspotting work on Japan and Korea eSIMs?
Yes, hotspot and tethering are included on eSIM plans for both countries, so you can share your data connection with a laptop or tablet. It draws from the same data allowance as everything else on your phone, so size up if you're planning to work from a laptop on either leg of the trip.
Ready to sort your phone for both countries? Head to the Japan eSIM plans and South Korea eSIM plans pages to compare current sizes and pricing, or check the cost comparison above to see whether a combined bundle beats buying separately for your trip.
Sources
Information checked 27 September 2026. Entry rules, fees and local details change - confirm anything important with the official source before you travel.