What you will learn in this article

• The most common reasons for an invalid lease agreement

• How to tell whether invalidity applies to the whole contract or just part of it

• How to proceed if you discover invalidity

• Why prevention is cheaper than fixing the consequences

When a lease agreement can be invalid

A contract is generally invalid if it lacks essential elements or contains terms contrary to law. For residential leases, the most common cases are:

• Missing required details – e.g., precise identification of the rented premises (address, apartment number, floor area).

• Contrary to law – provisions that circumvent or violate statutory rules (e.g., an unlimited contractual penalty for late rent payments).

• Signed by an unauthorized person – for example, the lease was signed by someone who is not the owner and has no power of attorney.

• Form issues – while the law allows oral agreements for residential leases, certain provisions (e.g., fixed-term duration) without written form may create legal uncertainty.

Note – sometimes only part of the contract is invalid (so-called partial invalidity), and the rest remains in force.

Case from practice

A client signed a lease agreement for an apartment that a friend had found online. It did not state the apartment number or the floor area, only the address of the building. Later, the landlord claimed the lease applied to a different unit in the building and demanded she move out. The court ultimately ruled the lease invalid due to the uncertain subject matter – and the client had to find new housing within three weeks.

Lawyer’s advice

An invalid lease doesn’t mean you have no rights at all – but it does mean legal uncertainty and often the inability to claim damages or recover your deposit without complicated legal proceedings. The best defense? Prevention. Have your contract reviewed by a lawyer before signing, especially if it was drafted “off the cuff.”