Which figure does the Kaution get calculated from?

For residential leases, BGB §551 caps the deposit at three months' rent excluding operating costs. For a monetary deposit, you are entitled to pay it in three monthly installments.

Is electricity part of the Warmmiete?

Check the written breakdown and ask whether apartment electricity and internet need separate contracts. Do not infer inclusion from the word “warm”.

The listing says 'warm' — does that mean everything is covered?

No. Check exactly which operating costs and heating charges are included, and which bills are separate. Ask your legal office about any broadcasting-fee exemption that applies to your status.

Housing

Kaltmiete vs Warmmiete: what's the difference on a German lease?

By Boris™ editorial · 2 min read · Sources

Quick answer

Kaltmiete is the base rent. Warmmiete usually adds operating costs and heating, but it does not necessarily cover every household bill. Ask for a written breakdown of what the lease includes and which utilities you must arrange separately.

Kaltmiete vs Warmmiete at a glance
Category	Kaltmiete (cold rent)	Warmmiete (warm rent)
What it covers	The apartment only — no utilities	Base rent plus the costs expressly included in the lease
Includes heating	No	Usually yes, as a separate line
Includes electricity	No	Often separate — check the lease
Includes internet	No	Often separate — check the lease
Used for the Kaution cap	Yes — 3 months of Kaltmiete (BGB §551)	No

What Nebenkosten actually covers

Ask the landlord for a written list of operating costs included in the lease. Confirm heating, hot water and shared building costs, and identify any utilities you must arrange separately.

How to read a listing without getting caught

Compare the full monthly total, including bills outside the quoted warm rent. Ask for the base rent, included charges and separate contracts in writing; do not estimate the total using a fixed percentage of cold rent.

Prepayments and annual accounting

Ask whether your lease uses operating-cost prepayments or a flat charge. Keep the lease, payment records and annual statements; ask housing or legal assistance to review any disputed bill before relying on a general deadline.

Frequently asked

Which figure does the Kaution get calculated from?: For residential leases, BGB §551 caps the deposit at three months' rent excluding operating costs. For a monetary deposit, you are entitled to pay it in three monthly installments.
Is electricity part of the Warmmiete?: Check the written breakdown and ask whether apartment electricity and internet need separate contracts. Do not infer inclusion from the word “warm”.
The listing says 'warm' — does that mean everything is covered?: No. Check exactly which operating costs and heating charges are included, and which bills are separate. Ask your legal office about any broadcasting-fee exemption that applies to your status.

Last recorded review: 2026-08-30. Requirements can change; confirm with the linked source or responsible office. Boris is independent of the DoD.

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