What does a kilowatt hour of heat really cost: gas, oil, district heating or heat pump?

The short answer

A kilowatt hour of heat from a gas boiler in an apartment building costs around 12 cents in energy in 2026, and 15 cents once boiler and maintenance are included. After this autumn’s price jump, heating oil comes to more than 21 cents at full cost, district heating to 15.6 cents on the market average, and a heat pump to between 15 and 19 cents depending on the electricity price and any grant.

These ranges come from a fully disclosed worked example, not from a measurement. But they show where most comparisons go wrong: the tariff price on the bill is not the price of heat.

Why is the tariff price not the price of heat?

Gas and oil are billed as fuel, district heating as finished heat, and a heat pump via electricity, which it turns into several times as much heat. Putting these prices side by side compares three different things. They only become comparable after three conversions:

1. Efficiency: A gas condensing boiler does not turn 100 kilowatt hours of gas into 100 kilowatt hours of heat in the heating circuit. In the example below I use 93 per cent for gas and 92 per cent for oil. For the heat pump it is the seasonal performance factor (Jahresarbeitszahl, JAZ): at 3, one kilowatt hour of electricity produces three kilowatt hours of heat.
2. Capital: The boiler, the heat pump and the tank cost money that has to be earned back over their service life. In the district heating price, the supplier’s capital is already included.
3. Operation: Maintenance, chimney sweep, repairs. The district heating customer pays for these through the price as well.

For landlords, the gross price is what counts, because VAT on letting residential property is generally not deductible. A business entitled to deduct input VAT calculates net.

What do the energy sources cost in autumn 2026?

Energy source	Price	Source, as of	per kWh of fuel/electricity
Natural gas, apartment building	11.17 ct/kWh	BDEW, average 2026 so far, data as of 08/2026	11.17 ct
Heating oil	€172.64/100 l	EU Weekly Oil Bulletin, 5 October 2026	17.18 ct
District heating, blended price apartment building	15.6 ct/kWh	AGFW/price transparency platform, reference date 1 April 2026	15.6 ct (finished heat)
Household electricity (for comparison)	37.0 ct/kWh	BDEW, average 2026 so far, data as of 08/2026	37.0 ct

All figures are gross prices. The conversion for heating oil comes from the German emissions reporting ordinance (EBeV): 0.845 tonnes per 1,000 litres and 42.8 gigajoules per tonne give 10.05 kilowatt hours per litre.

Two caveats belong with this. The BDEW gas price is an average of tariffs available since January; according to BDEW, procurement costs have risen since the Iran war and the price is trending upwards, so the current level is more likely above it. And there is no official average for heat pump electricity: BDEW explicitly excludes storage heating and heat pump tariffs from its electricity price analysis. I therefore calculate with two assumptions, 22 and 27 cents, and recommend inserting your own tariff.

District heating is also a local product. According to AGFW, almost all recorded sales lie between 12.5 and 17.5 cents; the blended price of 15.6 cents applies to a 160-kilowatt connection. Smaller buildings often pay more per kilowatt hour because the standing charge is spread over a smaller volume.

What does heat cost in a building with twelve flats?

The worked example is deliberately simple and fully disclosed. Building: 12 flats, around 900 square metres, 120,000 kilowatt hours of heat demand per year. Capital: 4 per cent interest over 20 years, giving an annuity factor of 0.0736. Investment (assumptions, replace with your own quotes): gas condensing boiler €35,000, oil condensing boiler €30,000, air-to-water heat pump €150,000. Maintenance: €1,200 a year for gas and oil, €1,500 for the heat pump.

Option	Energy €/year	Capital €/year	Maintenance €/year	Total €/year	ct per kWh of heat
Gas boiler (129,032 kWh gas)	14,413	2,575	1,200	18,188	15.2
Oil boiler (12,984 l heating oil)	22,415	2,207	1,200	25,822	21.5
District heating (blended price, excluding connection costs)	18,720	–	–	18,720	15.6
Heat pump, JAZ 3, electricity 27 ct	10,800	11,037	1,500	23,337	19.4
Heat pump, JAZ 3, electricity 22 ct	8,800	11,037	1,500	21,337	17.8
Heat pump, JAZ 3, electricity 22 ct, capital −30 %	8,800	7,726	1,500	18,026	15.0

The heat pump has by far the lowest energy costs: 7.3 to 9 cents per kilowatt hour of heat, against 12 cents for gas and 18.7 cents for oil. In the example it loses this lead through debt service. Only when its capital share falls by around 30 per cent, for example through a grant, does it draw level with the gas boiler. Which subsidy rates apply since the funding guidelines were revised is covered in a separate guide; in the example the reduction is deliberately calculated as a number without reference to any programme.

How much CO₂ price is in these figures?

At the first auction of national emission allowances on 1 July 2026, the clearing price was at the top of the corridor, 65 euros per tonne (DEHSt). Using the EBeV emission factors, that is around 1.40 cents gross per kilowatt hour of natural gas and 20.7 cents per litre of heating oil. In the example building it amounts to around 23 tonnes and €1,810 a year for gas, and almost 35 tonnes and €2,690 for oil. The CO₂ price is already included in the tariff prices above; it is not added on top.

For a twenty-year comparison it is nonetheless the most important open item, because it is incurred anew every year for gas and oil boilers and only indirectly, via the electricity price, for the heat pump.

What follows for owners and businesses?

On paper, the gas boiler is still the cheapest single option in autumn 2026, but only just, and it carries the greatest price risk: fuel and CO₂ price make up almost 80 per cent of its costs. For the heat pump it is the other way round; the investment decides. After the price jump since February, oil is by far the most expensive option.

1. Establish heat demand: Work out consumption in kilowatt hours from the fuel bills of the last three years and convert it to heat using the efficiency.
2. Insert your own prices: Gas price from a current offer, not from the old contract; for the heat pump, ask for a tariff with a separate meter.
3. Obtain investment quotes: At least two quotes per option, including ancillary work such as the electrical connection or the chimney.
4. Calculate full cost: Energy, capital and maintenance per kilowatt hour of heat, with an interest rate and term that suit your building.
5. Test sensitivity: What happens with a 20 per cent higher gas price, 20 per cent less grant, a seasonal performance factor of 2.7 instead of 3? The option that stays ahead in all three cases is the robust decision.