Lower your rent. We do the maths and write the letter.

The mortgage reference rate is 1.25 %, unchanged since 2 September 2025. If your rent was set when it was higher, you may ask your landlord for a reduction.

Check it in two fields

CHF
Without ancillary costs.
Lease start or last rent adjustment.

Free and without sign-up. You only pay CHF 39 if we send the letter for you. Next reference-rate announcement: early December 2026.

Check lease for free
PDF or photo · up to 10 MB per file
Drop files here
or
Lease, photo or letter from your landlord or property manager · multiple files allowed

Key contract details are detected automatically.

Check is free – you decide what happens next.

No lease available?
Enter details manually Privacy-friendly – no upload needed. Approx. 3 minutes.

Three steps, about five minutes

  1. Upload your lease

    A PDF or phone photos of the lease, plus the last rent adjustment if you received one. No lease to hand? Enter the figures yourself.

  2. Check the figures

    We read net rent, reference rate, last adjustment and termination dates, and show what you can claim and by when the letter has to arrive.

  3. Sign, we send it

    All tenants sign on screen. We print the letter and send it to your landlord by registered mail, and you get the tracking number.

This is the letter your landlord receives

Short and correct: it cites the new reference rate and asks for the reduction at the next termination date, with 30 days to reply. It goes out in the language of the place where the flat is: German, French or Italian.

You keep the calculation. For the example flat it looks like this:

Sample calculation
Net rent todayCHF 2'780.00
Reference rate 1.75 % → 1.25 %5.66 %
less inflation (40 % of CPI)−0.49 %
less general cost increases−0.83 %
Lower rent per monthCHF 120.65

Example figures. Your result depends on your lease; the landlord may raise objections.

Anna und Marco Beispiel, Musterstrasse 12, 8003 Zürich

Immobilien Muster AG
Postfach
8021 Zürich

Zürich, 1. November 2026

Einschreiben · Mietzinsherabsetzungsbegehren – Musterstrasse 12, 8003 Zürich

Sehr geehrte Damen und Herren

Den Medien konnte ich entnehmen, dass der hypothekarische Referenzzinssatz gesenkt wurde und aktuell bei 1.25 % liegt.

Ich ersuche Sie, meinen Nettomietzins auf den nächsten vertraglichen Kündigungstermin hin entsprechend herabzusetzen. Gleichzeitig bitte ich Sie um eine schriftliche Bestätigung innert 30 Tagen.

Sollten Sie meinem Herabsetzungsbegehren nicht oder nur teilweise entsprechen können, bitte ich Sie, mir Ihre Gründe innert der gleichen Frist mitzuteilen.

Freundliche Grüsse

Anna BeispielMarco Beispiel

One price, only when the letter goes out

CHF 39 once

Checking your lease, the calculation and a reminder when the reference rate falls again cost nothing.

Check my lease

Included for CHF 39

  • The letter, filled in with your lease details
  • On-screen signature for every tenant, also from different phones
  • Printing, envelope and registered mail to your landlord
  • Tracking number and a PDF copy by email
  • Your rent watched for twelve months

What we look at in your lease

Whether you can claim a reduction depends on a handful of facts in the lease. These are the ones we read and check.

Net rent
The rent without ancillary costs. Only this part goes down.
Reference rate in the lease
The rate your rent is based on. If it is missing, we look up the one in force back then.
Last adjustment
Date and reason of the last rent change. Inflation and costs are counted from here.
Indexed or graduated rent
These leases follow other rules during their fixed term.
Termination dates
They decide from when the lower rent applies and by when the letter has to arrive.
Ancillary costs
Kept out of the calculation; you can check them with our guide.

What happens to your lease

A lease contains names, addresses and signatures. We keep only what the check and the letter need.

Only after your consent
Documents are read once you have confirmed the privacy notice.
Deleted after 30 days
Uploaded documents are deleted automatically, or earlier with one click.
Read by an AI service
To extract the figures, documents go to our AI provider, for that purpose only.
No legal advice
The result is a calculation, not a lawyer's review of your case.

Questions we often get

Yes. The first check estimates your possible rent reduction. You only pay CHF 39 if you actually want us to create and send the rent-reduction request.
We create your personalised rent-reduction request based on your confirmed contract data, collect your digital signature and send it to your landlord or property manager by registered mail via Swiss Post. You receive the PDF copy, delivery tracking by email and 12 months of rent monitoring. No printing, no post office visit.
No. We handle printing, enveloping, addressing and posting as registered mail. You receive the tracking number by email.
Directly online – with a mouse, trackpad or finger on your smartphone. If several tenants are named in the lease (e.g. couples, flat shares), you can add co-signatories via QR code without them needing an account.
We monitor the Swiss mortgage reference rate for you. If it falls further, we notify you automatically and you can submit a new request.
No. You upload your lease, we extract the relevant data and guide you step by step through the check.
Ideally your lease and the most recent adjustment letter. If anything is missing, we tell you exactly what.
No. The result is an estimate based on your documents and Swiss tenancy law logic. The landlord may raise objections or offset other factors.
No. mietzins-senkung.ch is not a law firm and does not replace individual legal advice. For legal questions, contact a tenants' association, a conciliation authority or a specialist lawyer.
Yes. We support Swiss leases in German-speaking Switzerland; French and Italian are coming soon.
Your document is processed for automatic extraction and deleted by default after 30 days. Details are in the privacy policy.

Find out in two minutes whether your rent can go down

Upload the lease or enter the figures. If a reduction is possible, we prepare the letter; if not, you have lost nothing.

Upload my lease

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