Notice period Basel-Stadt: terminate your Swiss lease correctly

Key facts

Residential lease

3 months notice

Commercial lease

6 months notice

Termination dates

End of any calendar month

Registered mail

Strongly recommended (BGE 143 III 15)

How to terminate correctly

1. 1

   Check the notice period and date in your contract

   Read your lease contract. In canton Basel-Stadt the statutory minimum notice applies — your contract may specify longer periods. What counts is the day the letter arrives at the landlord, not when you send it (BGE 143 III 15).

2. 2

   Calculate the latest send date

   Count back 3 months from your termination date. Add at least 7 days for registered-mail delivery. This prevents the letter from arriving one day too late.

3. 3

   Write the termination letter with all required information

   Address the letter to all landlords listed in the contract. State the rental apartment clearly (address, unit number if any), the desired termination date, and include your signature. For married couples, both spouses must sign (Art. 169 Civil Code).

4. 4

   Send by registered mail and keep receipt for 5 years

   Send by registered mail. This is the only way to prove when it arrived at the landlord. Keep the delivery receipt for at least 5 years — legal deadlines for a potential conciliation procedure run that long.

Special rules in canton Basel-Stadt

• Notice must ARRIVE (not just be sent) before the deadline — allow 2–3 business days for postal delivery.
• Send by registered mail (Einschreiben) for proof of receipt.
• Older Basel leases may specify March 31 or September 30 as termination dates — check your contract carefully.
• Always verify the exact termination dates written in your specific lease agreement.

Legal basis: OR Art. 266a–266o; VMWG

Frequently asked questions

When can I terminate my lease in Basel-Stadt?

You can terminate your lease in canton Basel-Stadt at any time, provided you respect the 3-month notice period. Termination takes effect on the next permitted termination date. What matters is when the letter arrives at the landlord — not when you send it (BGE 143 III 15).

Do I have to send the termination by registered mail?

Registered mail is not legally mandatory — but strongly recommended. Only registered mail lets you prove when your letter arrived at the landlord. Per BGE 143 III 15, the arrival date counts, not the sending date. Keep the delivery receipt for at least 5 years.

What happens if I miss the notice period?

Miss the deadline and you stay a tenant for another 3 months — until the next possible termination date. At CHF 2,000/month rent, that's 6’000 CHF extra. A mistake makes the termination at the desired date invalid — with no way to retract.

Can I terminate early?

Yes, under CO Art. 264. You must present a solvent and suitable replacement tenant willing to take over the lease on the same terms. The landlord may only reject a replacement for important reasons (BGE 119 II 36).

Which conciliation authority is responsible?

The conciliation authority at the location of your rental is responsible. In canton Basel-Stadt that is Staatliche Schlichtungsstelle für Mietstreitigkeiten. The procedure is free of charge per CO Art. 274a and CCP Art. 113 para. 2 lit. c — conciliation is mandatory before filing a lawsuit.