Spending a week in Japan and a week in South Korea? You can buy one regional eSIM with data for both stops, or a separate country plan for each. The cheaper-looking option is not always the better fit: 10GB shared across a trip is more flexible than 5GB reserved for Japan plus 5GB reserved for Korea.
We compared three regional packages and two real pairs of local plans for one traveler using either 10GB or at least 20GB over 14 days. The prices are public euro prices observed on September 25, 2026, before coupon codes. The plan you choose must explicitly include your destination and remain valid through the last day of the trip.
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Quick Verdict: One Regional Plan or Two Local Plans?
For this seven-day Japan plus seven-day Korea itinerary, start with Nomad eSIM APAC’s 14 Countries Plan. Its shared 10GB/30-day plan costs €18.30, less than the €19.99 pair of local 5GB plans below. Its 20GB/45-day package is €30.49 during a public sale, effectively tied with two Ubigi 10GB country plans at €30.50. The regional plan lets you use the 20GB wherever you need it.
If the Nomad sale ends, its displayed 20GB regular price is €34.85. Two €30.50 local plans then save €4.35, provided 10GB in Japan and 10GB in Korea will be enough. Airalo and Saily also cover both countries; their costs and validity are compared below.
Table of Contents
What a 14-Day Japan and South Korea Trip Costs
This compares one traveler spending seven days in each country. Regional plans share data across both stops; two local plans have separate Japan and Korea allowances. Prices are for the complete purchase, with no coupon applied.
Full trip price: one regional plan or two local plans
| Option | 10GB trip | 20GB+ trip |
|---|---|---|
| Nomad eSIM APAC 14 countries · shared data |
€18.30 10GB · 30 days |
€30.49 sale 20GB · 45 days Regular €34.85 |
| Airalo Asialink Asia · shared data |
€21.50 10GB · 15 days |
€34.50 20GB · 15 days |
| Saily Asia and Oceania Shared data |
€31.99 10GB · 30 days |
€43.49 25GB · 60 days |
| Two local plans Separate country balances |
€19.99 Japan 5GB + Korea 5GB |
€30.50 Japan 10GB + Korea 10GB |
The 5GB + 5GB local pair is Ubigi Japan plus Saily Korea; the 10GB + 10GB pair is Ubigi in both countries. Saily’s higher regional tier is 25GB, not 20GB. Airalo’s 30-day shared options cost €22.50 for 10GB and €35.00 for 20GB, adding a timing buffer for €1 and €0.50 respectively. Nomad’s 20GB sale and the €30.50 local pair are effectively tied; a shared balance is the deciding difference.
Three Regional eSIM Plans for Japan and South Korea
These regional packages list both countries and let one eligible data allowance follow you across the border. Select the exact regional variant: a provider’s Japan-only product, a differently sized Asia variant or a general “from” price is not interchangeable with the plan compared here.
1. Nomad eSIM APAC: Best Overall for This Route
Choose Nomad eSIM’s APAC 14 Countries Plan and confirm that its country list includes Japan and South Korea. The fixed-data 10GB package lasts 30 days at €18.30. Its 20GB package lasts 45 days at a public sale price of €30.49; the displayed regular price is €34.85. Either duration covers the assumed two weeks after activation. The allowance is shared, so 12GB in Japan and 8GB in Korea fits the 20GB regional package.
The selected APAC country list names KDDI au and SoftBank in Japan, and SK Telecom, KT olleh and LG U+ in South Korea. The checked 20GB plan details allow hotspot sharing and eligible add-ons; this is a data plan without a conventional local phone number. Nomad says the plan begins when it connects to a supported destination network, or automatically after 60 days if unused. Listed partner networks and radio technology can vary by exact plan and location; we did not test speeds.
Choose it if you want one data setup and cannot predict your Japan/Korea split. Watch the sale: when 20GB returns to €34.85, a balanced pair of local 10GB plans costs less.
15% off an eligible first Nomad eSIM purchase
MYTECHGUIDE15
The listed €30.49 sale plan is excluded from this code. One eligible first purchase; also excludes sale plans, add-ons, unlimited plans, plans under US$5 and Thailand 50GB. Enter the code at checkout to confirm eligibility.
2. Airalo Asialink: A Shorter Validity Option
Airalo’s Asia fixed-data selector lists 18 countries and offers 10GB/15 days for €21.50 and 20GB/15 days for €34.50, with one allowance across included destinations. That is enough for this 14-day route if the clock begins on arrival and the trip ends within the plan window. A late flight or extra night leaves little room; the 30-day alternatives cost €22.50 and €35.00. Airalo says validity begins when the package first connects to a supported network.
Confirm Japan and South Korea in the exact package’s country list. We could not verify the partner carrier names for these specific Asialink fixed-data options, so the names shown on Airalo’s country-only products do not serve as evidence for this regional package. At Nomad’s €34.85 regular 20GB price, Airalo’s €34.50 15-day plan is €0.35 cheaper; its 30-day €35.00 plan has a longer buffer but costs €0.15 more.
3. Saily Asia and Oceania: More Validity and App Features
Saily’s 22-country Asia and Oceania package includes both Japan and South Korea. Its 10GB/30-day plan was €31.99 in our same-day EUR storefront record. For a traveler needing at least 20GB, the next fixed-data tier is 25GB/60 days at €43.49, with five extra gigabytes compared with the target, rather than a separate 20GB option.
Saily says its regional data activates in the first covered country when its eSIM and data roaming are enabled, or after 180 days if unused. Hotspot sharing and app top-ups are supported; optional app features include an ad blocker, web protection and virtual location. The regional product page does not name a specific Japanese or Korean partner carrier. This package supplies data; other number services, where offered, are separate products. Saily’s latest interactive EUR checkout could not be reached during our follow-up, so the stated EUR figures are from the earlier September 25 record.
10% off an eligible Saily eSIM purchase
MYTECHGUIDE
Apply to an eligible plan and confirm the offer at checkout. Code savings are not included in the comparison prices.
When Two Local Plans Work Better
If you expect 5GB in each country, the one-off Ubigi Japan 5GB/15-day plan is €10.00 and the Saily South Korea 5GB/30-day plan was €9.99 in our September 25 EUR record. Together they cost €19.99 for 10GB allocated as 5GB + 5GB. This pair uses different providers and separate country allowances; unused Korea data cannot rescue you if you use more than 5GB in Japan.
If you expect 10GB in each country, Ubigi Japan 10GB/30 days is €16.50 and Ubigi Korea 10GB/30 days is €14.00: €30.50 for two one-off purchases. Ubigi says its eSIM can be reused and these country plans begin on arrival, but they remain separate Japan and Korea balances. A reusable profile is not a shared 20GB regional package. Check in the app which purchased plan is active as you change countries.
These are illustrative priced baskets, not proof that we found the cheapest local offer on the entire market. Our Japan eSIM guide and South Korea eSIM guide go deeper on each destination.
Do not confuse a subscription with a one-off trip plan. Ubigi also lists a Japan + South Korea 5GB-per-month offer at €6 per month, with a three-month minimum before cancellation in the recorded terms. That means at least €18 across three billing cycles, while only 5GB is allocated in the first month. It does not deliver 10GB or 20GB for these two weeks at a €6 total price.
The Deciding Difference: Shared Data or Two Fixed Balances
Both a regional 10GB plan and two 5GB country plans add up to 10GB on paper. The difference is where you can spend it. A Japan-only balance ends at Japan; your Korea-only balance cannot cover a shortfall before you fly.
- 8GB in Japan, 2GB in Korea: a shared 10GB regional plan covers the trip. A local 5GB Japan plan runs out even though 3GB of the Korea allocation would remain unused.
- 5GB in Japan, 5GB in Korea: both approaches fit. Nomad’s checked €18.30 shared plan costs €1.69 less than our €19.99 two-country basket.
- 12GB in Japan, 8GB in Korea: a shared 20GB plan fits. Two local 10GB plans require extra Japan data while Korea’s balance still has 2GB left.
Estimate the data you need for maps, messaging and hotspot use before choosing a size; our guide to how much travel eSIM data you need can help. If you expect a lopsided split, price the likely local add-on as well as the base pair. If each country’s cap comfortably covers your use, the local purchase can become attractive when the regional sale ends.
How to Set Up Your eSIM and Cross the Border
- Before departure: check that your phone is unlocked, supports eSIM and can keep the profiles you plan to install. Use reliable Wi-Fi to install the chosen package and read its activation deadline. Installation, activation and validity are separate events for some providers.
- On arrival in Japan: select the travel eSIM for mobile data. Enable that line and data roaming where its provider instructs. Nomad starts on a supported destination connection or automatically after 60 unused days; Saily describes first-covered-country activation or an automatic start after 180 unused days. Check the exact purchased plan’s instructions.
- After landing in South Korea: a regional package that covers both countries should register on a supported local partner while using its remaining shared data. If you bought two country plans, select or activate your Korea purchase according to the app instructions. Allow time for registration and use the provider’s troubleshooting steps if data does not connect.
- Throughout the trip: monitor remaining GB and the expiry date. Airalo’s 15-day option has a particularly small buffer for a 14-day route; consider its 30-day version if your dates could move.
Nomad’s selected APAC country list names operators in both destinations, and the listed Ubigi country plans name their own local networks. Exact regional partners for Airalo Asialink and Saily were not established in this check. None of those names guarantees a particular speed or signal in a building, train or rural area. If you keep your home SIM active for calls or SMS, check its roaming charges and your phone’s data-line settings separately.
How We Compared These Plans
We compared fixed-data plans for one traveler spending seven days in Japan and seven days in South Korea. The 10GB scenario compares one shared regional allowance with two separate 5GB country plans. The larger scenario compares a shared 20GB allowance, or Saily’s next available 25GB tier, with two 10GB country plans.
Our comparison uses public EUR prices recorded on September 25, 2026, and official plan information from Nomad eSIM, Airalo, Saily and Ubigi. We compared the full trip cost, validity, activation rules and where each allowance can be used. Public sale prices are identified separately from regular prices; coupon savings and monthly subscriptions are excluded from the one-off price comparison.
We did not conduct independent speed tests. Exact partner networks for the regional Airalo and Saily packages could not be confirmed. Saily’s EUR prices come from an earlier storefront record on the same date; its latest EUR checkout was unavailable during our follow-up. Final prices may vary by locale and promotion.
Planning more stops? Our travel eSIM comparison covers broader options, while our eSIM by Destination guides help you choose plans for individual countries and regional routes.
Final Verdict
For a Japan-to-South-Korea trip lasting two weeks, Nomad eSIM’s APAC 14 Countries Plan is the best fit among the named options at the checked public prices. Shared 10GB costs €18.30, less than our €19.99 pair of local 5GB plans. Shared 20GB costs €30.49 while the sale runs, practically tied with Ubigi’s €30.50 local 10GB + 10GB pair, and lets you decide how to divide data as the trip unfolds.
If that sale disappears and 10GB per country is plenty, the two local plans save €4.35 against Nomad’s displayed €34.85 regular 20GB price. Airalo’s 15-day regional plan offers another shared 20GB option but has little date buffer; its 30-day version adds that buffer for €0.50. Saily is a longer-validity choice with 25GB as its next qualifying package. Choose the exact size, country list and validity that match your own dates and expected split.
Frequently Asked Questions
Will I need a new eSIM profile when I fly from Japan to South Korea?
A compatible regional plan that includes both countries can keep using its installed eSIM and remaining shared balance; your phone still needs to register on a supported Korean network. Two local purchases may require selecting the Korea data plan or profile in your phone or provider app. Follow the instructions for the exact purchases you made.
Is a 15-day package safe for a two-week itinerary?
It can fit 14 days if it starts when you arrive and lasts through your final day, but the buffer is small if flights shift. Airalo’s 30-day shared 10GB package costs €1 more than its 15-day equivalent; its 30-day 20GB costs €0.50 more in the checked EUR selector.
Does MYTECHGUIDE15 reduce Nomad’s €30.49 sale price?
No. The saved terms exclude sale plans, including the compared public 20GB offer. The code is for an eligible first purchase; its exact applicability must be confirmed at checkout. None of the comparison prices includes a coupon.
Do these regional data plans include a Japanese or Korean phone number?
The selected regional packages are data products; do not count on ordinary local calls, SMS or a local number as part of them. Calling apps can use mobile data. If you need a traditional number, look for a separately specified voice or number product and its own terms.
What if my phone cannot keep two eSIM plans active?
Check your device model and carrier-lock status. The number of installed and simultaneously active eSIMs varies by phone. One compatible regional data plan avoids switching between country purchases; for two local plans, check the app’s installation and activation steps before travel.
