Work out your share of a building's operating costs by living area and reconcile it against your advance payments, to see a refund or back payment.
How to use the Nebenkosten Calculator
Enter the building's total annual operating costs and total living area.
Enter your own living area and your monthly advance payment.
See your share, your annual and monthly costs, and any refund or back payment.
Frequently asked questions
Unless the contract says otherwise, operating costs are allocated by living area under the BetrKV. Your share is your area divided by the building's total area.
Some costs, especially heating and hot water, must be split mostly by consumption (50 to 70 %). This tool uses the area key, so for those items treat the result as an approximation.
It compares your share of the actual costs with what you paid in advance over the year. If you prepaid more than your share, you get a refund; if less, you owe a back payment.
The BetrKV lists allocable operating costs such as water, heating, waste, cleaning, garden and caretaker. One-off repairs and administration are generally not allocable.
This calculator estimates your share of a building's operating costs (Nebenkosten) using the living-area key, the default distribution method under the German Operating Costs Ordinance (BetrKV).
It then compares your share with the advance payments you made over the year and shows whether you can expect a refund or a back payment. It is an estimate to sanity-check a bill, not legal advice.
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