Wegweiser Small landlords · Renting out a flat, rights and duties Deutsch

📈 Rent increase up to the comparable rent

When and how you may increase the rent in an existing contract: deadlines, cap, consent.

rent increase § 558 rent increase cap rent index (Mietspiegel) consent lawsuit comparable rent

In brief

You may increase the rent up to the local comparable rent if it has been unchanged for 15 months. The tenant must consent.

  • Within three years the rent may rise by no more than 20 percent; in certain areas 15 percent.
  • You need a written justification, for example using a rent index (Mietspiegel).
  • The tenant has until the end of the second calendar month after receipt.
  • If they do not consent, you can sue within the following three months.

Step by step

  1. Check deadlinesRent unchanged for 15 months? Last increase at least one year ago?
  2. Prove the comparable rentJustify it with a rent index, information from a rent database, an expert opinion or comparable flats.
  3. Calculate the capCheck 20 percent (or 15 percent) in three years.
  4. Send the request for an increaseSend the request in a way you can prove and wait for the consideration period.

Deadlines

15 months
Rent must be unchanged at the time the increase takes effect§ 558 Abs. 1 BGB
20 percent in 3 years
Cap; 15 percent in areas determined by state ordinance§ 558 Abs. 3 BGB
3 further months
Landlord's deadline to sue after the end of the consideration period§ 558b Abs. 2 BGB
Watch out – common mistakes
  • If the tenant consents, they owe the increased rent from the start of the third calendar month after receipt of the request.
  • A request for an increase with formal errors can be repeated or cured in the legal dispute; the tenant keeps their full consideration period.
  • The reduced cap and the areas depend on the state; not researched.
In depth · legal basis, figures and practice – for advisers and professionals

Requirements, § 558 BGB

You can demand consent to an increase up to the local comparable rent if the rent has been unchanged for 15 months at the time the increase takes effect. The request can be made at the earliest one year after the last rent increase. The local comparable rent is formed from the customary rents for housing of comparable type, size, equipment, quality, location and energy efficiency that were agreed or changed in the last six years. Within three years the rent may not rise by more than 20 percent; the state governments can set 15 percent for areas where housing supply is at risk; such ordinances apply for no more than five years (§ 558 Abs. 3).

Consent and lawsuit, § 558b BGB

If the tenant consents, they owe the increased rent from the start of the third calendar month after receipt. The tenant can consent until the end of the second calendar month. If they refuse, you can bring an action for consent within three further months.

Justification

The means of justification (rent index, rent database, expert opinion, at least three comparable flats) are governed by § 558a BGB; the details were not checked against the wording here.

Who is responsible
  • Municipality (rent index, if available)
  • Haus & Grund
  • Amtsgericht (local court, action for consent)
Further reading
Rent level and rent brakeIndex-linked rent, graduated rent and modernisation

Quick questions

Worum geht es bei „Rent increase up to the comparable rent“?
When and how you may increase the rent in an existing contract: deadlines, cap, consent.
Which deadlines and figures matter?
  • 15 months: Rent must be unchanged at the time the increase takes effect (§ 558 Abs. 1 BGB)
  • 20 percent in 3 years: Cap; 15 percent in areas determined by state ordinance (§ 558 Abs. 3 BGB)
  • 3 further months: Landlord's deadline to sue after the end of the consideration period (§ 558b Abs. 2 BGB)
What should I do first?
  • Check deadlines: Rent unchanged for 15 months? Last increase at least one year ago?
  • Prove the comparable rent: Justify it with a rent index, information from a rent database, an expert opinion or comparable flats.
  • Calculate the cap: Check 20 percent (or 15 percent) in three years.
What do I need to watch out for?
  • If the tenant consents, they owe the increased rent from the start of the third calendar month after receipt of the request.
  • A request for an increase with formal errors can be repeated or cured in the legal dispute; the tenant keeps their full consideration period.
  • The reduced cap and the areas depend on the state; not researched.
Evidence
  • Bundesministerium der Justiz, Gesetze im Internet, § 558 BGB, retrieved 20 September 2026
  • Bundesministerium der Justiz, Gesetze im Internet, § 558b BGB, retrieved 20 September 2026
As of

September 2026 · Sources and method

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