What are Warmwasserkosten (hot water costs)?

Warmwasserkosten are the costs that arise from heating water used for everyday purposes such as showering, washing dishes and cleaning.
They are part of the operating costs (Betriebskosten) and are usually paid as part of the monthly advance payments on rent (Vorauszahlungen).

How are hot water costs calculated?

1. Based on actual consumption

This is the most common and fairest method.

• Individual hot water meters are installed in each flat to precisely measure the amount of hot water consumed.

• Costs are calculated based on the actual volume consumed, multiplied by the energy costs per cubic metre (m³) of heated water.

2. Distribution according to floor area or number of occupants

If no individual meters are installed, the costs are often distributed according to:

• the size (floor area) of the flat, or

• the number of occupants.

However, the Heating Costs Ordinance (Heizkostenverordnung) stipulates that costs should be allocated according to actual consumption whenever this is technically feasible and economically reasonable.

What factors influence the amount of hot water costs?

• The efficiency of the heating or hot water system

• The price of energy (gas, electricity or heating oil)

• Individual usage habits, for example:

  • How long and how often you shower

  • How often you use very hot water instead of just warm water

What is included in the hot water cost statement?

A transparent annual operating cost / heating cost statement for hot water should typically include:

• The total hot water consumption for the entire building

• The individual consumption of each flat

• The total energy costs for heating the water

• The distribution key used (e.g. according to consumption, floor area or a combination) and a clear breakdown of the costs for each flat

Tenant rights

• Tenants are entitled to inspect all original invoices and receipts held by the landlord or property management.

• If there are doubts about the correctness of the statement, they may submit a written objection within 12 months of receiving it.

• The method of distribution (e.g. by consumption or floor area) must be clearly explained in the annual statement.

How can you reduce hot water costs?

• Install water-saving shower heads and taps.

• Shorten shower times and use hot water more consciously.

• Use warm rather than very hot water whenever possible.

• Have leaking taps or pipes repaired promptly.

Who is responsible for maintenance of the system?

• The landlord is responsible for the maintenance, servicing and repair of the hot water and heating system.

• The tenant is responsible for proper use and must report faults or breakdowns without delay.

Practical tips

• Check whether your flat has its own hot water meter, and make sure that regular meter readings are taken.

• Keep copies of all statements and invoices relating to operating costs.

• If you suspect errors in the billing, consult a tenants’ association (Mieterverein) or seek legal advice.

Conclusion

The calculation of hot water costs (Warmwasserkosten) in Germany is governed by precise rules to ensure fairness and transparency. By understanding how these costs are calculated and by adopting smart consumption habits, you can avoid unexpectedly high bills, minimise disputes with your landlord and maintain better control over your housing budget.

The editorial and author team of the website strives to provide accurate information based on intensive research and multiple sources. Nevertheless, mistakes may occur or some information may not be fully verified. Therefore, the information presented here should be considered an initial point of reference, and you should always contact the competent authorities or professional advisers for binding and up-to-date information.