📈 Rent increase and modernisation

When and by how much the landlord may raise the rent and which deadlines you have.

rent increase cap consent modernisation special termination right rent index (Mietspiegel) hardship objection

In brief

The landlord may raise the rent up to the local comparative rent. Before that, the rent must have been unchanged for 15 months. Within three years it may rise by at most 20 percent. In areas with a tight housing market it is 15 percent.

You do not have to consent immediately. You have until the end of the second calendar month after receiving the letter. Check it calmly.

For a modernisation, the landlord must announce the works in text form at least three months in advance. He may then add 8 percent of the costs per year to the rent, but only up to certain caps.

In the case of a rent increase or a modernisation announcement, you can terminate specially within certain deadlines.

Step by step

Check the letterIs the reason given? Has the comparative rent been substantiated, for example by the rent index (Mietspiegel)?
Recalculate the limitsCheck the 15-month period and the 20 or 15 percent limit over three years.
Get adviceHave the letter checked by a tenants' association (Mieterverein) before the deadline expires.
ReplyConsent only to the justified part. Reply in writing and on time.

Deadlines

15 months

Rent must be unchanged before an increase up to the comparative rent§ 558 Abs. 1 BGB

2 calendar months

Time to consent after receipt; then 3 further months for the landlord to sue§ 558b Abs. 2 BGB

3 months

Minimum notice of a modernisation announcement in text form§ 555c BGB

End of the following month

Hardship objection to modernisation in text form, counted from receipt of the announcement§ 555d Abs. 3 BGB

Watch out – common mistakes

The cap is 20 percent in three years, 15 percent in tight areas.
Modernisation levy: 8 percent of the costs per year; caps of €3 per m² in six years, €2 if the starting rent is below €7 per m².
Special termination after a rent increase: until the end of the second month after receipt (§ 561 BGB).
After a modernisation announcement: special termination effective at the end of the month after next, to be declared by the end of the month following receipt (§ 555e Abs. 1 BGB).

In depth · legal basis, figures and practice – for advisers and professionals

Increase to the local comparative rent, § 558 BGB

At the time of the increase the rent must have been unchanged for 15 months. The request for an increase can be made at the earliest one year after the last increase. Within three years the rent may rise by at most 20 percent; in areas with a tight housing market, which the state governments designate for at most five years, by at most 15 percent. Deviations to the tenant's detriment are invalid (para. 6).

Consent and lawsuit, § 558b BGB

If the tenant does not consent by the end of the second calendar month after receipt, the landlord can sue for consent. The action must be brought within three further months.

Modernisation, §§ 555c, 555d, 559 BGB

The landlord must announce the measure in text form at the latest three months before it begins (type, scope, start, duration, expected rent increase and future operating costs). He should point out the form and deadline of the hardship objection. The tenant must communicate hardship grounds in text form by the end of the month following receipt of the announcement. Under § 559 Abs. 1 the annual rent can be increased by 8 percent of the costs incurred. Under § 559 Abs. 3a the monthly rent may rise by at most €3 per m² of living space within six years, and by at most €2 per m² where the starting rent is below €7 per m². For the installation of a new heating system (§ 559e cases) a special cap of €0.50 per m² in six years also applies. Under § 536 Abs. 1a, rent reduction is excluded for three months in the case of energy-efficiency modernisation.

Special termination rights

Under § 561 BGB, in the case of an increase under §§ 558 or 559 the tenant can terminate, by the end of the second month after receipt, effective at the end of the month after next; the increase then does not take effect. Under § 555e Abs. 1 BGB he can terminate extraordinarily effective at the end of the month after next, to be declared by the end of the month following receipt of the modernisation announcement.

Planned change

According to the Bundestag, the government draft "Mietrecht II" provides for raising the limit for the simplified procedure for modernisation from €10,000 to €20,000. Not current law (as of September 2026).

Who is responsible

Tenants' association (Mieterverein, review of the letter)
Local court (Amtsgericht, in an action for consent)
Municipal rent index office (Mietspiegel, where available)

Quick questions

Worum geht es bei „Rent increase and modernisation“?

When and by how much the landlord may raise the rent and which deadlines you have.

Which deadlines and figures matter?

15 months: Rent must be unchanged before an increase up to the comparative rent (§ 558 Abs. 1 BGB)
2 calendar months: Time to consent after receipt; then 3 further months for the landlord to sue (§ 558b Abs. 2 BGB)
3 months: Minimum notice of a modernisation announcement in text form (§ 555c BGB)
End of the following month: Hardship objection to modernisation in text form, counted from receipt of the announcement (§ 555d Abs. 3 BGB)

What should I do first?

Check the letter: Is the reason given? Has the comparative rent been substantiated, for example by the rent index (Mietspiegel)?
Recalculate the limits: Check the 15-month period and the 20 or 15 percent limit over three years.
Get advice: Have the letter checked by a tenants' association (Mieterverein) before the deadline expires.

What do I need to watch out for?

The cap is 20 percent in three years, 15 percent in tight areas.
Modernisation levy: 8 percent of the costs per year; caps of €3 per m² in six years, €2 if the starting rent is below €7 per m².
Special termination after a rent increase: until the end of the second month after receipt (§ 561 BGB).

Evidence

Bundesministerium der Justiz, Gesetze im Internet, § 558 and § 558b BGB, retrieved 20 September 2026
Bundesministerium der Justiz, Gesetze im Internet, § 559, § 555c, § 555d, § 555e BGB, retrieved 20 September 2026
Bundesministerium der Justiz, Gesetze im Internet, § 561 BGB, retrieved 20 September 2026
Deutscher Bundestag, hib report on the tenancy law bill (deliberation on 9 July 2026), retrieved 20 September 2026

As of

September 2026 · Sources and method

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