Check your claim
Enter your rent and the date of the last adjustment. The app calculates under federal law (Art. 270a CO + VMWG art. 13) including inflation and cost increases. 1:1 with the rent calculator of the Zurich courts.
≈ 2 min · free
Lower rent in 2 minutes
Get back
Get back
what you're owed.
The Swiss reference rate has dropped. You probably have a right to lower rent. RentReducer does the math in 2 minutes and mails your reduction request to your landlord with one tap.
Claim check + rate alert freeLetter from CHF 9.90A-Mail includedNo subscription
On a laptop? Scan with your phone:
App Store
Google Play
GDPR-aware
Data stays on your device
Swiss made
RentReducer
Rent history
Current
CHF 1'920
New (from Jun 1)
CHF 1'847
Reference rate
1.25 %
Data and law from official Swiss sources
BWO
BFS
Fedlex / CO
VMWG art. 13
ZH rent calculator
How it works
01
02
03
Three steps. No printing. No post office.
Enter your rent and the date of the last adjustment. The app handles the rest: from the calculation to your landlord's mailbox.
One tap to send
The app generates your reduction request with your finger-signature, hands it off encrypted to our Swiss postal partner, and mails it as A-Mail or registered. You get a push confirmation.
≈ 3 sec · from CHF 9.90Auto-reminders
Landlord doesn't reply? RentReducer reminds you after 14, 30 and 60 days. With one tap you fire the right follow-up: reminder, document request, or conciliation request.
automatic
Why we built this
Swiss tenants miss out on millions every year.
Only a fraction actively claims. Most because the writing feels like work: searching templates, doing the math, calendar reminders, chasing silence.
9 in 10
tenants don't claim
Only 12 % actively ask for a reduction, even though about half are entitled. Source: ZKB study 2026.
CHF 73
average monthly saving
For a typical 2.5-room flat at CHF 1'920. The letter pays for itself in the first week.
2 min
from open to ready-to-send
No templates, no Word docs, no printer. Push notification when the letter is on its way.
What sets RentReducer apart
Private. Precise. With one tap.
What makes RentReducer different from a Word template.
Court-grade calculation
RentReducer uses federal source data (BWO reference rate, BFS national CPI) and reproduces the official Zurich-courts rent calculator down to the cent. Including inflation, cost increases and an affordability check.
Privacy-first
Your data stays encrypted on your device. No account, no cloud DB. Only the finished PDF is handed encrypted to our Swiss postal partner.
Free rate alert
Push notification when the Swiss reference rate drops. No sign-up, no subscription. You can use the app purely as an early-warning system, that's perfectly fine too.
Four languages
App and letters in German, French, Italian and English. You pick a language, the app calculates, Swiss Post delivers.
From request to conciliation
From the initial reduction request through reminders and document requests to a conciliation announcement. Every follow-up letter is in the app, one tap away.
Price
Popular
No subscription. Less than 1/3 of your first month's saving.
The claim check is free. You pay only when you mail the letter, and even then only once per letter.
Free
CHF 0
unlimited use
- Check your claim in 2 minutes
- Rate alert when the reference rate drops
- Rent history + savings counter
- Data locally encrypted, no account needed
Perfect to dip in. If you have no claim, you pay nothing.
Letter mailing
CHF 9.90 – 29.90
once per letter · A-Mail included
- Reduction request as a legally compliant PDF
- Print + delivery by Swiss postal partner
- Your own finger-signature, captured in the wizard
- Auto-reminders + follow-up letters available
Add-ons (optional, à la carte):
Registered with tracking+ CHF 7.90
Follow-up reminder / document request (via Pingen)CHF 6.90
Follow-up conciliation as registered mail with lease photo and prior letters attached (or DOCX download)CHF 6.90 + 7.90
The letter price scales with your monthly saving — about a third.
Save little, pay little. Save more, pay a touch more, but never above CHF 29.90.
CHF 9.90 / 14.90 / 19.90 / 24.90 / 27.90 / 29.90 — depending on how much you save.
Frequently asked
What you'd want to know before you start.
Do I even have a claim?
If your last rent adjustment was based on a higher reference rate than today's, then yes, most likely. RentReducer calculates this automatically under Art. 270a CO and VMWG art. 13. You just enter your current rent and the date of the last adjustment.
The claim check itself is free. If the result is zero, you pay nothing.
What does the app actually cost?
The app is free. Claim check and rate alert stay free. You only pay for mailing the letter: a one-time CHF 9.90 to 29.90 depending on your monthly saving. Included: letter generation, A-Mail print and delivery by our Swiss postal partner.
Optional: Registered with tracking (+ CHF 7.90). Follow-up letters at CHF 6.90 each — reminder and document-request go out automatically via Pingen. The conciliation letter also goes from the app, as registered mail (+ CHF 7.90) with your uploaded lease photo and all prior letter copies attached. Prefer to mail it yourself? You can also download it as a DOCX.
Is RentReducer an official government app?
No. RentReducer is an independent app and is not affiliated with, operated by, or endorsed by the Swiss Confederation, any canton, public authority or court. All official data and legal references come from official Swiss sources. See the Sources block below.
RentReducer does not replace legal advice. For legal questions, contact a cantonal tenants' association or a lawyer.
What happens with my data?
Your rent and contract data stays encrypted on your device. We operate no cloud database and you don't need an account. Only the finished PDF of your letter is handed encrypted to our Swiss postal partner so it can be printed and delivered.
Details are in the Privacy Policy.
How accurate is the calculation?
Cent-accurate against the rent calculator of the Zurich courts. We use the official data sources (BWO reference rate, BFS CPI) and reproduce the formula from VMWG art. 13 including inflation, cost increases and an affordability check.
When the federal data is updated upstream, the app picks it up automatically and recalculates with the new values on next open.
What if my landlord doesn't reply?
RentReducer reminds you automatically after 14, 30 and 60 days. At every reminder you can fire the right follow-up letter with one tap, by status: reminder, document request, or conciliation letter. Each follow-up letter costs CHF 6.90. Reminder and document-request go via Pingen with A-Mail included. The conciliation letter also goes straight from the app as registered mail (+ CHF 7.90) with your uploaded lease photo and prior letter copies attached — or you can download it as a DOCX and mail it yourself.
If you go to conciliation, the app helps you with the directory of the cantonal conciliation authority (source: BWO).
What devices does RentReducer run on?
iPhone (iOS 15+) and Android (9+). Works on phones and tablets — the larger tablet screen just gives you more room to type.
Sources and disclaimer
All from official Swiss sources.
RentReducer links directly to the underlying federal data and legal references. You can verify every value in the app yourself.
BWO
Mortgage reference interest rate
Federal Office for Housing, primary data source (German)
BFS
National Consumer Price Index
Federal Statistical Office, for the inflation component
CO
Tenancy law: CO art. 269 ff., esp. 270a
Swiss Code of Obligations (Fedlex)
VMWG
Ordinance on residential and commercial premises
VMWG art. 13, calculation formula
SB
Conciliation authorities directory
BWO, cantonal addresses (German)
ZH
Tenancy law information from the Zurich courts
Verification reference (in German)
RentReducer is an independent app. It is not affiliated with, operated by, or endorsed by the Swiss Confederation, any canton, public authority or court, and it does not represent any government entity.
The app is not legal advice and does not replace an attorney. For legal questions, contact a cantonal tenants' association or a lawyer.