【2025 Version】Comparison of Short-term Prepaid SIM

photo by mroach

A smartphone is a must-have item when you travel. You use it to search destination, manage your schedule, and many other purposes. But you need to get it connected to the internet, of course. You can use the roaming service of your cell phone network provider, but that normally costs a fortune. To use your smartphone in Japan without worrying about costs, the best way is to get a SIM that can be used in Japan instead of roaming. In particular, prepaid SIM can be purchased and used instantly therefore best suit short-term visitors. Most prepaid SIM is for data use only, but instead, there is no need to open an account or anything. This column will compare prepaid SIMs for travellers that are sold at airports.

Smartphones commonly used in Japan

To use your overseas model device with a prepaid SIM card in Japan, your device must be SIM-free and suitable to Japanese communications standards. The followings are examples of smartphones commonly used in Japan that can also be purchased worldwide.

• Apple iPhone
• Samsung GALAXY（Global Model）
• Sony Xperia（Global Model）
• HUAWEI nova（Global Model）

Japan uses 4G LTE and 5G networks. Most modern smartphones are compatible to Japan’s networks, but some old ones are not. It is a good idea to enquire your mobile phone provider whether your phone is suitable to be used in Japan. If your model is unfit to Japanese standards, don’t be sad; you can rent a portable Wi-Fi router.

Things to Consider When Choosing a Prepaid SIM

Duration

Prepaid SIM is typically designed in order for convenience of tourists, then the validity periods tend to be short. A SIM card with the shortest period is valid for 7 days. The longer a validity period is, the larger data supply is given and the higher the price becomes. It is recommended to purchase a SIM card that covers the entire period of your stay in Japan.

Data Recharge

Some SIM plans are data-rechargeable and others are not.  If you are staying in Japan for a short period of time and will use data a lot, purchase a data-rechargeable one. By the way, you need to recharge your prepaid SIM before you run out of data, otherwise you need to connect to Wi-Fi to recharge.

Data Capacity

The most important thing when choosing a prepaid SIM is data capacity. Most SIMs come with fixed data size to be used throughout validity period, but some SIMs have capped daily data usage. Data supply of prepaid SIMs is limited except for SIMs that allow unlimited data usage. It is recommended to use a prepaid SIM with a combination with public Wi-Fi.

Plans

Most prepaid SIMs provide only mobile data. There are a few prepaid SIMs that allow phone calls but these are only available at retailers or online stores, not at airports. In addition, SIM plans with phone calls are more costly than data only ones. You may want to get a SIM with phone calls only if you want to make phone calls in Japan frequently.

Where to purchase

Prepaid SIM are available various locations across Japan such as international airports, convenience stores, tourist information centers and home electronics stores. For tourists, the best place to purchase a prepaid SIM would be shops in airports.

What you can do with 1GB of data

To choose the right plan for your travel, it is important to know what you can do with your mobile phone with 3GB of data.

• Blousing website: 1,800 pages (approx. 36 hours)
• Email (text only)/instant messages: 1,050,000 messages
• Email with attachments: 6,000 messages
• Downloading/streaming music: 600 songs
• Downloading/streaming movie (normal): 6 hours
• Downloading/streaming movie (HD): 1.5 hours
• Skype: 90 hours (voice call), 12 hours (video call)
• Online radio: 48 hours
• Downloading/updating apps: 75 times
*The above is an estimate and may change depending on*The above is an estimate and may change depending on the situation.

Comparison of SIM Cards Available for Purchase at the Airport

※Actual price varies by store. 

Summary

If you want to use large size of data

If you use a large volume of data, a plan with unlimited data, which are Unlimited Japan Prepaid SIM, Japan Prepaid SIM, AnyFone Japan, and Wi-Ho! Prepaid SIM is best for you. The validity period can be selected from 7 days, 15 days, and 30 days which is adequate to cover a short trip. These are most suitable for those who want to enjoy data-consuming activities such as watching movies or playing games without worrying about data capacity. Also, 10GB/15GB plan of Japan Travel SIM and AnyFone Japan had a good size of data even though it is not unlimited.

If you want to top up data

Of SIM cards available at airports, only Japan Travel SIM offers a recharge service which ranges from 500MB to 5GB. The SIM prices are rather law. If you want to save costs on your phone but want to have an option to recharge just in case, Japan Travel SIM is the best deal for you.

If you want to keep the costs low

Among prepaid SIMs sold at airports, Japan Travel SIM 3GB plan offers the lowest price. Also, Prepaid SIM for Travel has 3GB plan. These plans offer rather small data and a long usage period of 30 days. Also, they only costs around 3,000 yen. If you effectively use free WiFi, 3GB is more than enough. Japan Travel SIM also offers recharge options in case you run out of data. However, recharge might be a little expensive. Also, TRE SIM 3GB plan offers a low price of 3,000yen but this one is not rechargeable.

If you want a good customer service

Among Most SIM cards sold at airports are data-only SIMs with no phone calls. Only DATA&VOICE offers a phone call service but costs more than other SIMs. these prepaid SIM plans, Wi-Ho! Prepaid SIM offers unlimited data plans and customer support in Japanese and English in a case of unexpected incident. Prepaid eSIM, Japan Travel SIM, and AnyFone Japan offers a variety of plans with many SIM type options including eSIM.

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