How households were heated in 2021
The 2021 census asked every household in England and Wales what type of central heating it had. The Office for National Statistics published the results in January 2023. Mains gas dominated: 74% of households used mains gas and nothing else.
| Heating type | Households |
|---|---|
| Mains gas only | 74% of households |
| Electric only | about 2.1 million (about 9%) |
| Oil only | 865,940 (about 3%) |
| Renewable energy only | 98,730 (under 1%) |
| No central heating | 367,130 (1%) |
The census counts heat pumps under "renewable energy", along with other renewable systems, so the renewable figure is the closest it gets to a heat pump count. Fewer than one household in a hundred relied on renewable heating alone on census day.
What heat pumps have been replacing
The Boiler Upgrade Scheme records the heating each grant-funded heat pump replaced. For England and Wales between May 2022 and September 2026, the government's statistics show:
| Previous heating | Share of installations |
|---|---|
| Mains gas | 55% |
| Oil | 18% |
| No previous heating | 13% |
| Direct electric | 10% |
| LPG | 3% |
| Coal | 1% |
Two things stand out against the census. Oil is over-represented: it heated about 3% of households in 2021 but accounts for 18% of grant-funded heat pumps. And 13% of heat pumps went into homes that had no previous heating system, which the grant rules allow in some cases. Gas homes, the large majority, account for just over half.
How much heat homes use
Ofgem publishes typical domestic consumption values, used for price-cap comparisons. From July 2026, its medium figure for gas is 9,500 kWh a year, down from 11,500, with low and high figures of 6,000 and 14,000. Those figures cover all gas use, including cooking and hot water, and describe averages, not any particular home. They are a sense of scale, not a basis for sizing a heat pump, which needs a heat-loss calculation.
What the data means for a heat pump decision
- If you heat with gas, you are in the majority, and the running-cost comparison is close; the heat pump's real efficiency and your tariffs decide it.
- If you heat with direct electric heaters, a heat pump's heat costs a fraction as much per kWh at the same electricity price.
- If you heat with oil or LPG, you are in the group that has moved to heat pumps fastest relative to its size; compare your fuel's price per kWh of heat with the calculator.
The cost per kWh of heat calculator turns your own tariff into a like-for-like comparison.
Reading the two sources together
The census and the grant statistics measure different things at different times. The census counts every household on one day in March 2021; the grant figures count only heat pumps paid for by one scheme, over a period of more than four years, in England and Wales. So they cannot be combined into a single rate of change. What they do show together is the scale of the starting point: a country heated overwhelmingly by gas, with heat pumps so far concentrated in homes moving off oil and direct electric heating relative to how many of those homes there are.
Northern Ireland and Scotland are not in either set of figures used here. Scotland's heat pump funding comes through Home Energy Scotland, which has its own terms.
For a household deciding now, the useful number is not the national picture but its own: the fuel it uses, its price per kWh, and the heat its home needs. The calculator and a heat-loss calculation supply those.