Even if you rent an apartment in Japan and pay the rent properly, you cannot simply decide on your own to rent the unit out to someone else. Living in a property you have rented and allowing another person to use it as their own residence are two different things.
Under Japanese law, a tenant generally may not transfer the lease or sublet the property without the landlord’s consent. For example, you cannot simply move somewhere else, let another person live in the apartment, and collect rent from them without permission. If the lease specifically allows subletting, or if the landlord has formally agreed to it, the situation is different. The first thing to check is the rental agreement.
Having a friend or family member stay for a few days is usually not viewed in everyday life as “subletting” the apartment. A lease may still contain its own rules about additional occupants or long-term guests, so if there is any doubt, asking the landlord or property management company is the safest approach.
The situation changes considerably if you use a service such as Airbnb to host strangers for short stays and charge them money. That is no longer simply a matter of letting a friend sleep over. You are using the apartment to provide paid accommodation. If the property is being used under Japan’s private lodging system, the required notification procedures must be followed, and the landlord must have consented to the property being used for that purpose.
Even the landlord saying “yes” may not be enough by itself. In an apartment building or condominium, the building’s management rules may prohibit short-term lodging, so those rules also need to be checked.
In other words, having a friend stay for a few nights and taking money from strangers to stay in the apartment are completely different matters, even though both involve someone else sleeping there. If you are considering subletting or short-term lodging, check the lease first. If anything is unclear, ask the landlord or management company. Renting an apartment does not give the tenant the right to sublet it or use it for short-term lodging at will.
