Nebenkosten in the Rental Contract: No Advance Payment Without an Explicit Agreement

Many tenants assume a Nebenkosten advance payment automatically comes with the rent. In fact, it's only valid if the rental contract explicitly provides for it — otherwise, a completely different rule kicks in.

What the law actually requires

Under § 556 (2) BGB, landlord and tenant can agree that operating costs are billed either as a flat rate or as an advance payment. That agreement has to be in the Mietvertrag, and any advance payment can only be set at a reasonable amount. If the contract is missing such a clause entirely, the agreed rent automatically counts as an Inklusivmiete, where all operating costs are already included and no separate annual statement follows.

Why this matters in practice

If your rental contract doesn't clearly regulate an advance payment, but your landlord still sends you a Nebenkostenabrechnung with an additional charge at year end, it's worth taking a close look at the actual contract text. Without an effective agreement, there's no legal basis for a Nachzahlung, no matter how plausible the individual cost items look.

What "a reasonable amount" means

The law explicitly requires that an agreed advance payment be set at a reasonable level. Deliberately setting it too low, just to make an apartment look cheaper in listings, contradicts this principle, even though no fixed monetary cap exists in the law. As a rough benchmark for a realistic range, the nationwide Betriebskostenspiegel from the Deutscher Mieterbund puts the average at €2.67 per square meter a month.

What to watch for with a flat rate

If a flat rate is agreed instead of an advance payment, the rental contract also has to clearly state which cost types it covers. Only then can it later be checked whether an increase to that flat rate — which is only permitted under specific conditions per § 560 BGB — was actually justified correctly.

What to check before signing

Check whether the rental contract clearly distinguishes between cold rent and Nebenkosten, and whether it explicitly mentions an advance payment or a flat rate. If that distinction is missing entirely, raise it with the landlord before signing, to avoid confusion at the first annual statement.

If you want to know how landlords are legally allowed to split those Nebenkosten between tenants once a valid agreement exists, see our guide on square meter vs. person-based billing. And for what happens if your landlord tries to raise your prepayment or flat rate later, our guide on when a Nebenkosten increase is actually valid explains the rules.

Frequently Asked Questions

Does the Nebenkosten advance payment have to be stated in the rental contract?

Yes, under § 556 (2) BGB an explicit agreement is required, otherwise the rent counts as an Inklusivmiete with no separate annual statement.

What happens if my rental contract has no advance payment clause but I still get a Nachzahlung demand?

Without an effective contractual basis, the landlord generally has no right to demand additional payment.

Is there a legal cap on how high the advance payment can be?

No, the law only requires a reasonable amount, without a fixed ceiling. The Deutscher Mieterbund's Betriebskostenspiegel serves as an orientation point.