Tokyo minpaku M-number lookup: verify the license before you pay

A licensed Tokyo minpaku displays an M-number on its listing page. It looks like M130051307. You can verify it against the city's published registry in about 30 seconds. If the listing has no number, or the number isn't in the file, do not pay. Cancellations of unlicensed minpaku stays are common and last-minute. Platforms refund at their discretion.

The lookup is free. The registry is in English on the per-ward PDF list. The Tokyo Metropolitan Government updates the file monthly.

This guide shows where to find the number on Airbnb and Booking.com, how to read the metro registry, and four legitimate operator types where the lookup returns nothing on purpose.

---

Where the M-number lives on the listing

Airbnb and Booking.com both surface the registration number, but in different places.

Airbnb lists the registration number in the "Registration number" line under "Things to know" near the bottom of the listing. For licensed minpaku, the value is M followed by 9 digits. The Tokyo prefix is 130. So a Tokyo minpaku reads M130 + 6 digits, e.g. M130051307. Airbnb also displays the host's "Hosting category" and the 180-day cap, both inside the same section. If the value is "Exempt" or the field is missing, the listing is not registered as minpaku and the M-number lookup will not apply.

Booking.com displays the registration number in the property's "Important information" panel and in the cancellation-and-prepayment section. The label reads "Registration number under the Housing Accommodation Business Act" or the Japanese equivalent. The format is the same M130-prefix value.

Direct-booking sites (operators who run their own websites) are required to display the number on the page advertising the unit. The 民泊 (minpaku) law requires it under Article 13 of 住宅宿泊事業法 (jūtaku shukuhaku jigyō-hō — the 2018 Housing Accommodation Business Act). If the operator's site omits the number, that is itself a sign of an unlicensed listing.

Reading the metro registry

Tokyo Metropolitan Government's Bureau of Industrial and Labor Affairs publishes the full registry of licensed minpaku. The URL is sangyo-rodo.metro.tokyo.lg.jp/application/tourism/minpaku/list. The page is in Japanese, but the per-ward PDFs are bilingual. Each ward publishes its own file. The metro page links to all 23.

The PDF columns are: notification number, notification date, address of the certified private lodge, and two ward-ordinance flags. A typical row reads:

M130051307   05/23/2025   1-43-16, Uehara, Shibuya-ku, Tokyo, Japan

Run this check in three steps:

1. Copy the M-number from the listing.
2. Open the PDF for the listing's ward (Shibuya, Setagaya, Shinjuku, etc.). The metro page lists all 23.
3. Use your PDF viewer's find function (Ctrl-F or Cmd-F) and paste the number. The match should land on the listing's actual address.

If the number is in the file and the address matches the listing, the registration is real. If the address does not match, the operator may have switched units after registration, which is itself a violation. Ask the operator before paying.

The list is updated monthly. Each ward's PDF carries an "as of" date in the header. A registration filed yesterday may not be in this month's PDF. If your listing's number is not in the current file, ask the operator for the date of registration. Numbers issued in the last 30 days will appear in next month's update.

Reading the format

The M-number itself encodes ward information. The leading M is the registration class. The 130 is the prefecture code (13 = Tokyo, 0 = the metropolitan branch). The next two digits are the ward code. The last five digits are a sequential number within that ward.

So M130051307 in Shibuya tells you: this is the 51,307th notification filed at the Tokyo metro level, in the Tokyo registry. The numbers are issued in chronological order. A six-digit sequence above 050000 was filed in 2025 or later. A five-digit sequence below 010000 was filed in 2018, when the law came into force. This date pattern is sometimes useful when an operator claims a pre-COVID record but the number is freshly minted.

---

The four operators where the lookup returns nothing

A clean M-number is the gold standard for short-term legitimacy. But four other operator types in Tokyo are also legitimate, and none of them will appear in the M-number registry. If you run the lookup and find no record, the operator may still be legal — but only under one of these.

Ryokan-business operators (旅館業 — Hotel Business Act). This is the older, heavier license. It covers hotels, ryokan (traditional inn), kani-shukusho (簡易宿所 — simple lodging), and shukuhaku-shogyo (lodging house). The hokenjo (保健所 — public health office) issues it. There is no 180-day cap. The license number lives on a wall plaque inside the building, not in any single online registry. Ask the operator for the license-issuance ward and the file number; cross-check by phoning the ward's hokenjo. Apartment-hotels (Mimaru, Tokyu Stay, MIMARU Suites) all run under this license.

Tokku-minpaku operators (特区民泊 — special-zone minpaku). This is the special-zone framework under 国家戦略特区法 (kokka senryaku tokku hō — the National Strategic Special Zones Act). In Tokyo, only Ota Ward operates a tokku-minpaku regime, mostly because Haneda Airport sits inside the ward. Tokku-minpaku numbers are issued by Ota Ward directly, with the format 第◯◯◯号 (ninth-character number prefix, no M). The minimum stay is 2 nights and there is no 180-day cap. The lookup is on Ota Ward's site, not the metro list.

Residential mid-term operators. These are the operators Sakura House, Oakwood, Citadines, halfkey, and similar furnished-apartment companies run. The unit operates under 借地借家法 (shakuchi shakuya hō — Act on Land and Building Leases) using a 定期借家契約 (teiki shakuya keiyaku — fixed-term lease). The minimum stay is 30 nights. There is no license number to display. The legal floor is built into the contract, not the registration. If your stay is 30+ nights, an operator without an M-number is normal and legal: they're not running a hotel.

Corporate-housing operators. These are 法人向け (hojin-muke — corporate-only) furnished units leased en bloc to a single employer for staff rotation. The chain of contracts is corporate sublease, not a guest booking. No retail license is involved. These units never appear in any guest-facing registry. Bookings happen through the corporate housing department of a Japanese subsidiary or a global mobility provider.

A listing whose number is not in the metro registry, and which doesn't match any of the four above, is unlicensed.

---

What to ask before paying

Send this to the operator in writing before you transfer money. Save the email thread.

For an Airbnb-style stay under 30 nights:

1. What is the registration number for this listing, and on what licence (minpaku 180-day, ryokan, or tokku)?
2. Has the building's 180-day annual cap accommodated this many guest nights so far this calendar year? If yes, what is the remaining count for the dates I want?
3. If your registration is denied or cancelled before my stay, what is the refund schedule?

For an aparthotel under 30 nights:

1. Under which Hotel Business Act category does this property operate (hotel/ryokan, simple lodging, or lodging house)?
2. Is the license posted in the lobby, and may I have a photo before booking?
3. Is there a per-night cap or seasonal restriction set by the ward?

For a 30+ night furnished apartment:

1. The unit is on a fixed-term lease, not a hotel licence — please confirm this in writing.
2. May I see the contract template and a copy of your standard 重要事項説明 (jūyō jikō setsumei — explanation of important contractual matters) before paying?
3. What's the operator's company registration number (法人番号)? This is a 13-digit number issued by the National Tax Agency for any incorporated entity.

A clean operator answers these inside one business day. A defensive or deflecting answer is itself the answer to whether to book.

Verifying a 30+ night operator

For stays of 30 nights or longer, the M-number is not the right verification target. The fixed-term residential lease has no notification number to display. Ask for the operator's 法人番号 (hōjin bangō — corporate number, a 13-digit ID issued by the National Tax Agency to every incorporated entity) and confirm in writing that the contract is a 定期借家契約.

The corporate number is searchable at houjin-bangou.nta.go.jp. Type the operator's company name in Japanese or English. The result shows the registered address and date of incorporation. If the operator's website does not name a 法人番号 anywhere in the footer or contract, the entity may not be a registered company. That is its own warning sign.

---

Run the lookup before you pay

Do these in order, in the next 20 minutes.

1. Open the listing and copy the registration number. If it's missing or "Exempt," set the listing aside; do not book a sub-30-night stay without a number on file.
2. Confirm the format: M followed by 130 plus six digits for Tokyo. A different prefix means the listing is in another prefecture.
3. Open the metro registry at sangyo-rodo.metro.tokyo.lg.jp/application/tourism/minpaku/list and download the PDF for the listing's ward.
4. Search the PDF (Ctrl-F or Cmd-F) for the M-number. Confirm the registry's address line matches the listing's stated address.
5. If the number is missing, ask the operator which licence applies. Use the question list above for ryokan, tokku, or fixed-term lease.
6. If you'd like halfkey to compare a 30-day-or-longer mid-term shortlist, reply to this article's contact form with dates, ward, and budget.

The cost of paying for an unlicensed minpaku that gets cancelled mid-stay is a hotel rebooking at peak rate plus a forfeited deposit. The cost of running the lookup is the time it takes to read this paragraph.

---

— halfkey runs furnished Tokyo apartments on fixed-term residential leases of 30 days and longer. Browse listings for your dates.