Checking Your Nebenkosten (Utility/Operating Costs) Statement: The 10 Most Common Errors

Why you should check every Nebenkosten (utility/operating costs) statement

Studies show that around 50 percent of all Nebenkosten statements in Germany contain errors — at the tenant's expense. The average overpayment is 200 to 300 euros per year. Over the entire tenancy, this quickly adds up to four-figure sums. So it pays to look closely.

As a tenant, you have the right to review the statement and raise objections within twelve months of receiving it. Be sure to make use of this deadline.

Error 1: Late delivery of the statement

The landlord must deliver the Nebenkosten statement within twelve months of the end of the accounting period (§ 556 Abs. 3 BGB). If you only receive the statement for 2025 after 31 December 2026, you generally do not have to pay any additional charges. However, you are still entitled to any credit balance.

Error 2: Non-apportionable costs are charged

Not all costs may be passed on to tenants. The Betriebskostenverordnung (Operating Costs Ordinance, BetrKV) defines conclusively which types of cost are permitted. Impermissible items frequently appear:

• Administrative costs (property management, bank fees)
• Maintenance and repair costs
• Vacancy costs for unlet flats
• Costs for property management software
• The landlord's legal fees

Error 3: Wrong allocation key

The allocation key determines how the total costs are split among the individual tenants. Common errors: the floor area (Wohnfläche) has been calculated incorrectly, the number of occupants is wrong, or the key changes without notice. Check whether the key agreed in your rental contract is being applied.

Error 4: Costs are charged twice

Sometimes costs are charged both in the Nebenkosten statement and directly through the Kaltmiete (base rent) or separate flat-rate charges. Typical examples: property tax or building insurance appear in the statement even though they are already included in the rent.

Error 5: Breach of the principle of cost efficiency

The landlord is obliged to act economically (§ 556 Abs. 3 BGB). If individual cost items are disproportionately high — for example, overpriced caretaker services or winter road clearance — you can challenge them. Compare the costs with standard market prices.

Error 6: Faulty heating cost statement

The Heizkostenverordnung (Heating Costs Ordinance) requires that at least 50 and at most 70 percent of heating costs be billed based on actual consumption. Errors in meter readings, faulty measuring devices, or incorrect conversion factors regularly lead to incorrect statements.

Error 7: Access to supporting documents is refused

You have the right to inspect all receipts and invoices on which the statement is based (§ 259 BGB). If the landlord refuses this, the statement can be contested. Request the documents in writing and set a reasonable deadline.

Error 8: Unexplained cost increases

Always compare the current statement with the previous year. If individual items rise by more than 10 to 15 percent for no apparent reason, you should follow up. Calculation errors or unjustified cost allocations are often behind this.

Error 9: Wrong accounting period

The accounting period must be exactly twelve months. If the landlord shortens or extends the period without reason, the statement is formally defective. Exception: when you move in or out during the year, the costs are billed proportionally.

Error 10: Formal defects in the statement

A Nebenkosten statement must contain certain minimum information: the total costs per cost type, the allocation key, the tenant's share, and the advance payments made. If any of this information is missing, the statement is formally invalid.

What to do if you find errors

If you spot errors, you should object in writing within the twelve-month objection period. Describe the errors specifically and demand a corrected statement. KlarMiet helps you with this: upload your Nebenkosten statement and, within minutes, receive pointers to possible errors — as a basis for a conversation with a specialist lawyer.