Buying a Japan eSIM on Airalo costs more than it needs to. We put both sites' published prices side by side, plan for plan.
On 7 matching plans altesim.com came out cheaper than Airalo, by 46% to 61%.
How we compared
Both columns are the prices each site published on 11 September 2026, listed in US dollars. We used each site's actual selling price, not a struck-through list price.
Every comparison uses altesim.com's full price, ignoring the 10% site-wide discount it runs one day in three — the strictest reading against ourselves.
A "matching plan" means the same number of days and the same data allowance, with per-day plans compared only against per-day plans.
A detailed comparison: How does altesim.com stack up against Airalo?
| Plan | altesim.com | Airalo | You save |
|---|---|---|---|
| 7 days · 10GB total | US$7.04 | US$17 | 59% |
| 15 days · 10GB total | US$7.26 | US$17.5 | 59% |
| 30 days · 10GB total | US$7.48 | US$18 | 58% |
| 7 days · 5GB total | US$3.92 | US$10 | 61% |
| 15 days · 5GB total | US$4.13 | US$10.5 | 61% |
| 30 days · 5GB total | US$4.34 | US$11 | 61% |
| 30 days · 20GB total | US$13.45 | US$25 | 46% |
When travelling in Japan, the options for eSIMs are quite diverse. In this comparison between altesim.com and Airalo's Japanese eSIM plans, we found that altesim.com offers 7 plans that are cheaper than Airalo's, with savings ranging from 46% to 61%. The most significant difference is in the "7 days, 5GB total" plan, where altesim.com charges US$3.92 compared to Airalo's US$10, a saving of 61%. Although the savings decrease slightly with longer durations, the difference remains notable. For instance, the "10GB total" plan is 59% cheaper for 7 days and 58% cheaper for 30 days; the "5GB total" plan is 61% cheaper for both 7 and 30 days. If you're planning a trip to Japan, regardless of the length of your stay, altesim.com is a solid choice.
How to use a data-capped plan without running out midway
With a data-capped eSIM, you don't need to track your daily data usage, allowing for more flexibility on days when you use more data. When travelling in Japan, activities like using navigation, uploading photos, and streaming videos consume the most data. To avoid running out of data midway, estimate your needs based on your itinerary. Generally, if your accommodation has Wi-Fi and you mainly use data for maps and communication, 1GB per day should suffice. If you use navigation, upload photos, and occasionally stream videos, you might need around 5GB to 10GB for a week. If you share a hotspot with others or frequently stream videos or live stream, you might need around 20GB for 10 days. altesim.com's plans can help you stay connected in various scenarios.
What options does altesim.com offer on its Japan page?
altesim.com provides a wide range of Japanese eSIM plans, with a total of 218 options available, ranging from 1 day to 365 days. These plans are divided into data-capped and daily plans, ensuring that both short-term travellers and long-term visitors can find a suitable option. In addition to single-country plans, altesim.com also offers multi-country plans that include coverage for Japan. Across the entire site, altesim.com offers a total of 2,303 plans covering 84 destinations, so no matter where you travel, you can find a suitable plan.
How much data do you actually need in Japan? Three itineraries to match your needs
The data requirements for travelling in Japan vary depending on your itinerary. Itinerary A is for those whose accommodation has Wi-Fi and who mainly use data for maps and communication; in this case, 1GB per day is sufficient, corresponding to plans like "7 days, 7GB total" or "30 days, 30GB total". Itinerary B is for those who frequently use navigation, upload photos, and occasionally stream videos; in this case, you might need around 5GB to 10GB for a week, corresponding to plans like "7 days, 10GB total". Itinerary C is for those who share a hotspot with others or frequently stream videos or live stream; in this case, you might need around 20GB for 10 days, corresponding to plans like "10 days, 20GB total". It's important to note that the length of your trip will affect your data needs, so adjust your plan choice accordingly.
What are the advantages of altesim.com?
altesim.com's Japanese eSIM plans have several advantages. They are priced in US dollars, and you can choose to pay in your local currency at checkout, which is convenient for travellers from different countries. altesim.com's Japanese plans use the KDDI and SoftBank networks, support 5G, and allow you to create a hotspot to share with others, ensuring you have access to high-speed internet wherever you go. altesim.com's plans allow you to share a hotspot with your travel companions, so you and your friends can stay connected without worrying about network issues.
Three things to do before purchasing
Before making a purchase, there are three things you should do. First, check if your phone supports eSIM; recent iPhones, Samsung Galaxy S series, and Google Pixel phones do, but older models and some China-specific versions need to be verified. Second, check if it's a 10% off day; if so, you can save an additional 10%. Third, revisit the destination page to confirm the current price, as prices on all platforms can change at any time. By taking these steps, you can confidently make your purchase and enjoy the quality service provided by altesim.com.
Prices are as published on 11 September 2026 and can change at any time; check the page on the day you buy.