Operating Costs Calculator: Estimate Betriebskosten per Square Metre
How high are your operating costs (Nebenkosten), and is your second rent too high? Our free calculator estimates the monthly operating costs based on your living area, broken down by cost type using average values from the operating-cost index (Betriebskostenspiegel). With a traffic-light assessment for your apartment.
Last updated: June 2026
Estimated operating costs per month
€203.00
= €2,436.00 per year · 2.90 €/m² per month
Breakdown per month
Estimate based on national average values (operating-cost index, German Tenants' Association). Average around 2.17 €/m², upper range up to around 2.90 €/m² per month. Your actual costs can vary by region and building.
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Calculating operating costs: what the second rent really costs
Anyone renting an apartment pays more than just the base rent (Kaltmiete). On top come the operating costs (Nebenkosten/Betriebskosten), often called the second rent. They make up a substantial share of the monthly housing costs. With this calculator you estimate the operating costs per m² for your apartment and check whether your operating costs are too high.
On a national average, the warm operating costs come to around €2.17/m² per month. If all chargeable cost types apply, the figure can rise to about €2.90/m² per month. For a 70 m² apartment, that adds up to roughly €150 to €200 a month, or €1,800 to €2,400 a year on top of the base rent.
The values used here come from the operating-cost index (Betriebskostenspiegel) of the German Tenants' Association (Deutscher Mieterbund). These are national average values. Your actual costs depend on the region, year of construction, heating type and fittings of the building and can differ considerably.
Cold and warm operating costs: the difference
Operating costs fall into two groups. The cold operating costs cover all running costs except heating and hot water, that is property tax (Grundsteuer), water and sewage, waste collection, building cleaning, caretaker, garden maintenance, elevator, communal electricity, insurance and chimney sweeping.
The warm operating costs consist of heating and hot water. In many apartments they are the largest single item and depend heavily on energy prices. If you heat with your own gas boiler and bill directly with the supplier, this item does not appear in the operating-cost statement.
Which costs the landlord is even allowed to pass on is governed by the Operating Costs Ordinance (§ 2 BetrKV). It lists 17 cost types conclusively. Only these may be allocated to the tenants, and only where the allocation has been validly agreed in the tenancy agreement.
Operating-cost breakdown by cost type
The table below shows the average operating costs per cost type in euros per square metre and month. This way you can see which items weigh most heavily.
| Cost type | €/m²/month | At 70 m²/month |
|---|---|---|
| Heating & hot water(depending on the building) | 1.15 €/m² | €80.50 |
| Property tax (Grundsteuer) | 0.19 €/m² | €13.30 |
| Water & sewage | 0.38 €/m² | €26.60 |
| Waste collection | 0.17 €/m² | €11.90 |
| Street cleaning | 0.03 €/m² | €2.10 |
| Building cleaning(depending on the building) | 0.17 €/m² | €11.90 |
| Caretaker (Hausmeister)(depending on the building) | 0.21 €/m² | €14.70 |
| Garden maintenance(depending on the building) | 0.11 €/m² | €7.70 |
| Elevator(depending on the building) | 0.18 €/m² | €12.60 |
| Communal electricity / lighting | 0.06 €/m² | €4.20 |
| Property & liability insurance | 0.17 €/m² | €11.90 |
| Chimney sweeping | 0.04 €/m² | €2.80 |
| Other operating costs | 0.04 €/m² | €2.80 |
With the heating and hot water item, the total comes to around €2.90/m². Items marked (depending on the building) only apply if the relevant installation is present.
Typical operating costs by apartment size
How high the operating costs turn out depends above all on the living area. The overview below calculates with all cost types, that is the upper estimate range of around €2.90/m².
| Living area | Per month | Per year |
|---|---|---|
| 45 m² | €130.50 | €1,566 |
| 60 m² | €174.00 | €2,088 |
| 75 m² | €217.50 | €2,610 |
| 90 m² | €261.00 | €3,132 |
| 120 m² | €348.00 | €4,176 |
Tip: if you do not know your exact living area, the living-area calculator helps you determine it correctly under the Living Area Ordinance (Wohnflächenverordnung).
Allocation key: how the costs are distributed
So that every tenant in the building bears their fair share, an allocation key is needed. The three common allocation keys are:
- Living area: the default if nothing else is stated in the tenancy agreement. Costs are distributed in proportion to the square metres.
- Number of people: useful for consumption-related costs such as water or waste when there are no individual meters.
- Consumption: for individually metered costs, above all heating and hot water.
For heating costs, the Heating Costs Ordinance (HeizkostenV) requires that at least 50 to 70% of the costs be billed according to consumption. The rest may be distributed by living area. That way, whoever heats more also pays more. If there is no consumption-based billing, the tenant may reduce their heating cost share by 15%.
The operating-cost statement: deadlines and rights
During an ongoing tenancy you pay an advance payment every month. Once a year the landlord settles the actual costs. This results in either a back payment or a credit. Clear rules apply to this statement.
The landlord must deliver the statement no later than 12 months after the end of the accounting period (§ 556 para. 3 BGB). If it arrives too late, the landlord can generally no longer demand a back payment. A credit, however, must still be paid out to you.
As a tenant you have a right of inspection of the original receipts. If you disagree with the statement, you can raise written objections within 12 months of receipt. You should only make a back payment subject to reservation until the statement has been clarified.
Are my operating costs too high? How to check
A first reference point is the comparison with the operating-cost index. Divide your annual operating costs by the living area and by 12. If the result is significantly above €2.90/m² per month, a closer look is worthwhile. The traffic light at the top of the calculator does this calculation for you as soon as you enter your advance payment.
Also check whether non-chargeable items appear in the statement. The landlord may not pass on to the tenant:
- Administrative costs (account management, property management, postage)
- Maintenance and repairs (anything that preserves the fabric of the building)
- Reserves and one-off purchases
Since 1 July 2024 the following also applies: the costs of a cable TV connection can no longer be passed on across the board as operating costs. The so-called Nebenkostenprivileg has been abolished. Since then tenants decide on their TV connection themselves.
If, as a landlord, you want to know how the costs affect your yield, the rental yield calculator can help. And for a planned rent adjustment, it is worth looking at the rent increase calculator, since operating costs and base rent are considered separately.
Frequently asked questions about operating costs
On a national average, the warm operating costs (Nebenkosten/Betriebskosten) come to around €2.17/m² per month. If all chargeable cost types apply, the figure can rise to about €2.90/m² per month. For a 70 m² apartment that roughly corresponds to €150 to €200 a month. These values come from the operating-cost index (Betriebskostenspiegel) of the German Tenants' Association and are average values that can vary by region.
Only the 17 cost types listed conclusively in § 2 of the Operating Costs Ordinance (BetrKV) are chargeable. These include heating and hot water, property tax (Grundsteuer), water and sewage, waste collection, street cleaning, building cleaning, caretaker, garden maintenance, elevator, communal electricity, insurance, chimney sweeping and other running costs agreed in the tenancy agreement.
Warm operating costs are the costs for heating and hot water. All other operating costs, such as property tax, water, waste, caretaker or insurance, count as cold operating costs. The warm operating costs are often the largest single item and depend heavily on energy prices.
Administrative costs (property management, account management, postage), maintenance and repairs, as well as reserves and one-off purchases are not chargeable. The landlord bears these costs themselves. Since 1 July 2024, the costs of a cable TV connection are also no longer chargeable across the board.
With all cost types and the upper estimate range of around €2.90/m², the operating costs for a 70 m² apartment come to about €200 per month, or roughly €2,400 a year. If only the basic items without heating, elevator and caretaker apply, it is around €75 to €90 a month. The exact amount depends on the building and region.
The landlord must deliver the operating-cost statement no later than 12 months after the end of the accounting period (§ 556 para. 3 BGB). If they miss this deadline, they can generally no longer demand a back payment. A credit, however, must still be paid out to you.
Compare your costs per m² with the operating-cost index and check whether non-chargeable items appear in the statement. You have a right to inspect the original receipts and can raise written objections within 12 months of receipt. You should only make a disputed back payment subject to reservation until the statement has been clarified.
Under the Heating Costs Ordinance (HeizkostenV), at least 50 to 70% of the heating costs must be billed according to consumption, the rest by living area. That way, whoever heats more also pays more. If there is no consumption-based billing, the tenant may reduce their heating cost share by 15%.
No. The calculator provides an estimate based on national average values from the operating-cost index (Betriebskostenspiegel) of the German Tenants' Association. The actual operating costs depend on the region, year of construction, heating type and fittings of the building and can differ considerably. What is decisive is always your specific operating-cost statement.
No. Since 1 July 2024, the costs of a cable TV connection can no longer be passed on across the board via the operating costs. The former Nebenkostenprivileg has been abolished. Since then tenants decide for themselves whether and which TV connection to book.
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