How To Check If A Japanese Property Has An Unregistered Building

What "unregistered building" means

Every building in Japan is legally supposed to get a 表題登記 (hyoudai touki, "descriptive registration") once construction finishes — the initial filing that puts the structure's location, floor area (床面積), structure type, and roof material onto the record for the first time. Under the Real Property Registration Act (不動産登記法), this filing is generally required within one month of completion, and the same one-month deadline and filing duty falls on anyone who acquires ownership of a building that is still unregistered — including a buyer — running from the date they acquire it, not from the original construction date. Missing it can draw a fine (過料) of up to ¥100,000. Once the filing is made, the building gets its own registration record, separate from the land it sits on.

In practice, that filing does not always happen. Storage sheds, workshops, garages, and additions built onto an existing house are common candidates for being left off the registry entirely, particularly on rural land and older houses where enforcement has historically been loose. The result is a structure that is physically real and may be decades old, but has no registration record of its own — the registry may show only the land, or show a building with a smaller floor area than what is actually standing if an extension was never added to the filing.

Not every structure on a lot is even supposed to have its own building record, though. Registration practice generally expects a building to be fixed to the ground, enclosed enough to serve its purpose (walls and a roof, not just a frame or tarp), and put to a stable use. A small tool shed that is essentially a movable box, or an open-sided carport, can legitimately have no registration of its own without that being a case of 未登記建物 — so the first question is whether a given structure was ever expected to be registered before treating its absence from the record as a gap.

The reverse problem: a building that's registered but no longer there

The same gap runs the other way. When a building is demolished, the owner is generally supposed to file 建物滅失登記 (tatemono messhitsu touki, "building loss registration") within about a month, removing it from the record. If that filing never happened, the registry can still show a building that was torn down years ago — a registered structure with nothing behind it. This matters most if you are buying land specifically to build new: a stale registration on a building that no longer exists can still need to be cleared before construction or a future sale goes smoothly.

Why this matters for financing and resale

Japanese lenders generally require a building offered as loan collateral to be properly registered — an unregistered structure cannot be mortgaged in the normal way, even if it is genuinely part of what you are buying. It also becomes your problem at resale: a future buyer's own due diligence will turn up the same gap, so an unregistered building you inherited from the seller does not go away just because you didn't build it.

Here is a practical way to check before you get attached to a listing:

1. Get the building number (家屋番号, kaoku bangou) from the agent, not just the address or lot number. Building records are indexed by their own building number, which does not always match the land's lot number. Ordering with only a postal address or lot number risks failing to locate the correct record for reasons that have nothing to do with whether the building is registered.
2. Order the building registration record and confirm what a no-result actually means. See How To Order A Japan Property Registration Record In English for the ordering workflow. A no-result is consistent with the building being unregistered, but it is also consistent with a wrong or missing building number — treat it as a prompt to double-check the identifier with the agent before concluding the structure was never filed.
3. Decide whether the structure was ever expected to be registered. A permanent, enclosed structure with its own foundation is the kind of thing 未登記建物 applies to. A small movable shed or an open carport may simply fall outside what registration practice covers, so its absence from the record is not automatically a red flag.
4. Compare the registered floor area and structure to what is actually on site. If a building record exists but its floor area (床面積) looks smaller than the structure in the listing photos, or it does not mention a wing or workshop that is clearly there, an addition was likely never added to the filing.
5. Ask the agent directly about any structure you are unsure of. Rather than assuming every structure in a listing photo needs its own registration, ask which ones are permanent buildings and whether each is registered — this also surfaces cases the identifier alone might miss.
6. If a building record exists, check whether the structure is still standing. A registered building on a lot you plan to clear for new construction should still be there; if it was already demolished, ask whether 滅失登記 has been filed to remove it from the record.
7. Ask who is responsible for registering an unregistered structure before closing. This is sometimes handled by the seller's side before transfer, and sometimes left for the buyer to resolve afterward — get this in writing rather than assuming. Either way, once you acquire an unregistered building, Japanese law generally gives you one month from that date to file the 表題登記 yourself, so build the timeline for whoever handles it around that deadline rather than an open-ended "eventually."

The most common mistake is checking the land record, finding it clean, and assuming the buildings are automatically covered — land and buildings are registered independently in Japan, so a clean land record says nothing about the structures on it. A close second is treating a no-result on a building record request as confirmed proof of an unregistered building, when a wrong or incomplete building number produces the same no-result. The third is discovering the gap only when applying for financing, rather than during initial due diligence.

What the registry can and cannot tell you here:

• What it shows reliably: for a registered building, the floor area, structure type, roof material, number of stories, and date of completion recorded in 表題部.
• What it does not show: a structure's existence is invisible to the registry unless someone filed for it — there is no way to search the registry for "unregistered buildings on this lot." The only way to check is to order what should be the building's record and see whether it exists and matches what you can see on site, and a no-result only means the building is unregistered once you have confirmed the building number used for the request was correct.
• How to order the record: On Japan Property Research, locate the property and order the building registration record for ¥1,500 using its building number (家屋番号) if you have it — an address or lot number alone can fail to locate a building record even when the building itself is properly registered.

Fixing a genuinely unregistered building generally means bringing in a 土地家屋調査士 (tochi kaoku chousashi, "land and house surveyor") to survey the structure and file the 表題登記 before it can be mortgaged or cleanly resold. That is a real cost and a real delay, and it is not just a good idea: once you acquire the building, you generally have one month under 不動産登記法 to file, with a fine of up to ¥100,000 for missing that deadline — so factor the timeline in before you make an offer rather than after. Our Japan property due diligence checklist covers where this check fits alongside ownership, boundaries, and zoning.

FAQ

Can I still buy a property with an unregistered building? Yes, it is not illegal to buy one, but once you acquire it, the one-month filing deadline under 不動産登記法 runs from your purchase date, not the original construction date — buying an unregistered building does not reset the clock, it starts it for you. Missing that deadline can draw a fine of up to ¥100,000, so if you go ahead, plan to file the 表題登記 promptly rather than treating it as an open-ended project.

Does an unregistered building affect getting a mortgage? It can. Lenders generally want the building registered before accepting it as collateral, so an unregistered structure can complicate or block financing that depends on it.

How do I know if a shed or extension was ever registered? Order the building registration record using the building number (家屋番号), not just the address, and compare its floor area and description to what is physically on the lot. A missing record only points to an unregistered structure once you've confirmed the identifier was correct — a wrong or incomplete building number can produce the same no-result.

Does every shed or outbuilding need to be registered? No. Registration practice generally expects a structure to be fixed to the ground, enclosed, and put to a stable use before it counts as a registrable building. A small movable shed or an open carport can legitimately have no record of its own without that being a case of 未登記建物.

What if the registry shows a building that was already demolished? That means 建物滅失登記 (building loss registration) was never filed. It should generally be cleared from the record before you rely on the land being genuinely vacant for new construction or a clean resale.

Is this more common on akiya and rural land? Yes. Additions, outbuildings, and older structures on rural and low-value properties are the most common candidates for having never been filed, similar to how unregistered inheritance tends to cluster on the same kinds of properties.

Related guides:

• How To Read A Japanese Property Registration Record
• How To Check If A Japanese Property Has Unregistered Inheritance
• Akiya Guide For Foreign Buyers In Japan
• How To Order A Japan Property Registration Record In English
• Japan Property Due Diligence Checklist