03 (Tokyo)
03 is the area code for Tokyo. It is assigned to landlines mainly in central Tokyo (the 23 wards), with many calls originating from corporate offices, retailers, and public agencies.
Regional Characteristics
Tokyo's 23 wards form the political, economic, and cultural core of Japan and account for roughly 20% of national GDP. Each ward has its own industrial character: government offices cluster in Chiyoda, financial firms in Chuo, global corporate headquarters in Minato, and IT and entertainment companies in Shibuya and Shinjuku. The resident population is about 9.7 million, and daytime population including commuters exceeds 12 million. The 03 area code is widely used by main lines of corporations and public agencies, with callers spanning finance, real estate, IT, and government.
Common Nuisance Call Patterns
Cold calls pitching studio-condo investments in central Tokyo are frequently reported. Callers use lines such as "it works as a tax shelter" or "it builds your retirement assets" to spark interest, then aggressively push for an in-person appointment.
Callers claim to be from "an NTT-affiliated company" and pitch a line switch or plan review. In practice they are often resellers, and there are reports of them rushing the contract through without fully explaining the terms.
Scammers impersonate ward office or tax office staff and claim there is a "medical-fee refund" or a "tax overpayment," then direct the victim to an ATM. Public agencies never instruct anyone to operate an ATM over the phone.
Consumer Affairs Center
Tokyo Metropolitan Consumer Affairs Center
Frequently Asked Questions
Which area does the 03 area code cover?
03 is assigned to Tokyo's 23 wards. It is used for landlines in central Tokyo, including Chiyoda, Chuo, and Minato wards.
What should I do if I get an unknown call from an 03 number?
Start by looking up the caller on a phone number directory such as Denwa. If it is a business or public agency, you can match it against the official number on their website. If it looks suspicious, do not call back and consider blocking the number.
How can I reduce nuisance calls from 03 numbers?
Use your smartphone's spam filter or the spam-blocking service provided by your carrier. For landlines, combining caller ID with a dedicated nuisance-call blocking device is effective.
Is 03 ever assigned to mobile phones?
No. 03 is reserved for landlines. Mobile phones use the 070, 080, and 090 ranges. That said, some IP phone services do offer 03 numbers.