+81 Is Japan's Country Code
+81 is the country code assigned to Japan. When you place an international call, the country code goes in front of the number to show which country you are calling. The United States is +1, the United Kingdom is +44 and China is +86.
In other words, +81 90-1234-5678 is exactly the same number as 090-1234-5678 in Japan. The leading 0 has simply been replaced by +81. Once you know what the first digits of a phone number mean, you can tell at a glance what kind of number you are looking at.
Country codes are assigned to individual countries and territories by the ITU (International Telecommunication Union). Japan has +81, while neighbouring South Korea has +82 and China has +86. The country code system is defined by an international standard called E.164, which exists so that every telephone number in the world can be identified uniquely.
Why +81 Shows Up
The Call Came From Overseas
When someone outside Japan calls a Japanese number, the call may be displayed with +81 in front of it. It could be a family member travelling abroad, or a business contact overseas.
The Number Is Saved in International Format
If a number is stored in your contacts in +81 format, it will be displayed that way when the phone rings. Depending on the handset and the contacts app, a number you save may also be tidied up into international format on its own. That format is simply easier to live with when the same contact is used on both sides of a border.
It Is the Sender of a Scam SMS
An SMS that arrives from a number with +81 in front of it may well be a fraudulent message sent through a server outside Japan. Legitimate Japanese companies almost never send SMS with a +81 prefix. Treat a +81 message along the lines of "regarding the delivery of your parcel" or "your account has been suspended" as very likely fraud. Do not tap the link - look the number up instead, or check your account yourself through the company's official app or website.
How to Convert a +81 Number Back to a Normal One
All you do is replace +81 with 0. That works because the 0 at the start of a Japanese phone number is a marker called the domestic prefix, and in international call notation it is replaced by +81.
- +81 90-1234-5678 becomes 090-1234-5678 (mobile phone)
- +81 3-1234-5678 becomes 03-1234-5678 (landline in Tokyo)
- +81 6-1234-5678 becomes 06-1234-5678 (landline in Osaka)
- +81 120-123-456 becomes 0120-123-456 (toll-free)
- +81 50-1234-5678 becomes 050-1234-5678 (IP phone)
To go the other way and put a Japanese number into international format, replace the leading 0 with +81. You need this when you give your own number to a friend abroad, or when you register a phone number with an overseas web service.
Watch Out for Country Codes Other Than +81
If a call arrives with a country code other than +81, it came from outside Japan. If you were not expecting it, the safer choice is not to answer. Calling back costs international call rates.
- +1: United States and Canada (the same +1 is shared by a number of countries and territories)
- +44: United Kingdom
- +86: China
- +82: South Korea
- +63: Philippines
- +91: India
- +84: Vietnam
The calls that call for the most caution are those from country codes in Africa and the Pacific islands. The one-ring scam works by getting you to call back an expensive international number, with part of what you pay flowing back to whoever placed the call. Never call back a number with a country code you do not recognise. The safe approach is to search for the number and confirm who it belongs to before you do anything. Learning about the phone numbers that have disappeared from Japan also gives you a deeper feel for how the numbering system has changed over time.
Using +81 While You Are Abroad
When you call a Japanese number while travelling outside Japan, you use +81. For example, to call a home number in Japan (03-1234-5678) from abroad, you dial +81-3-1234-5678. On a smartphone, holding down the 0 key enters the "+" character.
If you receive a call on a Japanese mobile phone while you are abroad, the way international roaming works means the person taking the call can be charged as well. How much that costs, and when it applies, depends on your carrier and your plan, so it is worth checking your own contract before you travel. While travelling, switching to internet calls through apps such as LINE or WhatsApp keeps your phone bill down. Over Wi-Fi there is no call charge at all, so make the most of the Wi-Fi in your hotel or a cafe.
How to Save Numbers With +81
When you save a number in your contacts, storing it in +81 format is the convenient choice, because it dials correctly whether you are inside Japan or abroad.
- Recommended format: +81 90-1234-5678
- Works inside Japan too: on most handsets and networks, a number saved in +81 format is still handled as a domestic call when you dial it from inside Japan
- Works abroad as it is: dialled from overseas, the +81 makes sure the call reaches Japan correctly
Messaging apps that come from outside Japan, such as WhatsApp and Telegram, normally ask for your phone number with the country code in front of it (+81 format). It is worth including an update of these apps in your checklist for changing your phone number as well. If you expect to use apps like these, standardising your contacts on the +81 format makes everything smoother.
+81 and the E.164 Format
A form such as +81312345678, with no hyphens or spaces, is called the E.164 format. It is the international standard notation for telephone numbers laid down by the ITU, and it is what computer systems and databases use to handle phone numbers. There is no need to think about it in everyday life, but when you register a phone number with an overseas web service you may be asked to "enter the number with +81 and without hyphens".
Summary
+81 is Japan's country code, and the digits after +81 are an ordinary Japanese phone number. Replace +81 with 0 and you have the original number. Do be careful, though: an SMS with +81 in front of it may be fraud routed through a server abroad. Do not call back numbers with country codes you do not recognise, and respond only to numbers you were expecting. Occasions to use +81 come up more often than you might think, whether you are travelling or keeping in touch with friends overseas, so the conversion rule is worth remembering.