The conditions in Art. 270 OR
| Requirement | Detail |
|---|---|
| Deadline | 30 days after you take over the flat |
| Where | The conciliation authority for tenancy matters |
| Condition a | You felt forced to sign because of personal or family hardship, or because of the situation on the local housing market |
| Condition b | The landlord raised the starting rent considerably compared with the previous rent for the same flat |
| What is examined | Whether the rent is abusive under Art. 269 and 269a OR |
One of the two conditions, a or b, is enough.
When is a rent abusive?
A rent is abusive when it brings an excessive return or rests on a clearly excessive purchase price (Art. 269 OR). As a rule it is not abusive when it lies within what is customary in the place or neighbourhood, or when it is justified by higher costs or added services of the landlord (Art. 269a OR).
Find out the previous rent
You can ask the landlord to tell you the rent of the previous tenancy (Art. 256a OR). Ask in writing at the handover at the latest.
Cantons with a housing shortage can make the official form compulsory when a new lease is signed (Art. 270 OR). The form then shows the previous rent and the reasons for an increase. According to the directory for 2026 of the Federal Office for Housing (BWO), the form is compulsory in Basel-Stadt, Bern, Fribourg, Geneva, Lucerne, Zug and Zurich, and in parts of Neuchâtel and Vaud.
Steps
- Sign the lease and take over the flat. The 30 days start with the takeover.
- Ask for the previous rent, or read it on the official form.
- Compare: how much higher is your rent, and what reason is given?
- Send your request to the conciliation authority within the 30 days.
- Keep paying the agreed rent while the case runs. Ask a tenants' association or a lawyer about your chances before you file.
How aptari helps
aptari gives you numbers for the comparison in step 3. Median asking rents in the aptari feed on 9 November 2026, per square metre and month: Zurich CHF 39.60, Geneva 41.20, Lausanne 31.30, Bern 28.10, Basel 27.80. Asking rents are the rents shown in listings. They are not official statistics and do not replace the proof of local rents that an authority asks for, but they show quickly whether a flat sits far above what others ask.
This is general information, not legal advice.