Check Index Rent: Tenant Guide for Germany
Many existing tenants in Germany wonder whether an index rent was calculated correctly and how to verify the adjustment. This guide explains simple, practical steps so tenants can collect evidence, verify calculations and respond formally to the landlord. You will read which sections of the BGB are important, which deadlines must be observed and which local courts are responsible if a dispute arises. The language is intentionally clear and avoids legal jargon so tenants without a legal background can find concrete steps. At the end you will find a short how-to, frequently asked questions and official contact points in Germany, including practical tips for presenting documents.
What is an index rent?
With an index rent, the rent is tied to a price index (usually the consumer price index). The landlord adjusts the rent when the index changes; this must be agreed in the lease. Important legal provisions on tenancy and rent increases are found in the German Civil Code (BGB) §§ 535–580a.[1]
Which documents do tenants need?
Collect all relevant evidence before checking the calculation or contacting the landlord:
- Collect evidence: copy of the lease, index agreement, past rent statements, correspondence and receipts.
- Index data: the original source of the consumer price index used and the values for the relevant dates.
- Payment proofs: bank transfer receipts or account statements showing actual payments.
- Documentation: photos or logs if repairs or changes affected usability.
How to check the calculation step by step
Check the formula agreed in the lease and compare the index values the landlord used. Pay attention to rounding rules, timing of adjustments and any minimum/maximum limits in the agreement.
- Check the contract: read the index clause carefully and note the formula.
- Compare index values: request the exact index values and compare them with the official source.
- Verify the calculation: calculate the adjustment yourself and compare your numbers with the landlord's statement.
- Check formal errors: look for missing information or unclear rounding that could affect the amount.
What to do in case of discrepancies?
Contact the landlord in writing, explain your calculation and request correction or a transparent statement. Set a reasonable deadline for a reply. If no agreement is reached, the local court (Amtsgericht) is often responsible; rules of civil procedure are governed by the ZPO.[2]
Which forms and authorities are relevant?
There is no single federal "index rent lawsuit template", but the following official sources are important:
- Correspondence with the landlord: use an informal letter to set a deadline and request disclosure of the calculation.
- Statement of claim at the local court: if necessary, file a claim for eviction or payment disputes; procedural rules are in the ZPO.[2]
- Attach evidence: include copies of the lease, account statements and your calculation.
FAQ
- When may the landlord adjust the index rent?
- Only if the index clause was agreed in writing and the adjustment follows the agreed index values.
- Must I accept a written adjustment immediately?
- You do not have to accept it immediately; check the calculation and request a detailed breakdown if unclear.
- Where can I turn if the landlord does not cooperate?
- In unclear cases you can contact the competent local court or seek legal advice; in disputes the higher instances are the regional court and possibly the Federal Court of Justice (BGH).
How-To
- Gather the lease, past statements and payment proofs.
- Note the exact index clause and formula in the contract.
- Obtain the official index values and document them.
- Recalculate the adjustment and compare with the landlord's notification.
- Formally write to the landlord, attach your calculation and set a deadline for clarification.
- If there is no response, consider filing a claim at the local court.
Key Takeaways
- Document everything precisely before challenging an adjustment.
- Understand the contractual formula and the official index used.
