Royal estates face 10 million pound EPC bill: what the C by 2030 rule means for every landlord

What the rule actually says

From 1 October 2030, every privately rented home in England and Wales must reach EPC band C, or the new equivalent, unless a valid exemption is registered. The current minimum of EPC E has applied since April 2020, but the higher standard is part of the government's Warm Homes Plan. A single 2030 deadline now applies to all tenancies, replacing the earlier plan for 2028 and 2030.

The current minimum standard, EPC E, has been in force since April 2020 under the Energy Efficiency (Private Rented Property) Regulations 2015. The move to band C is part of the government's Warm Homes Plan, with the final policy position set out in the January 2026 consultation response.

The single 2030 deadline replaced an earlier plan for 2028 for new tenancies and 2030 for existing tenancies. All tenancies now share one date, simplifying the compliance timeline for landlords.

The costs and the cap

The government has set a cost cap of 10,000 pounds per property, reduced from an earlier 15,000 pound proposal after sector lobbying. Lower caps apply to homes valued under 100,000 pounds. Government estimates put the average upgrade at 6,100 to 6,800 pounds, though industry estimates run higher for older stock. Homes let without required improvements face penalties of up to 30,000 pounds.

The 10,000 pound cap was confirmed after consultation, with the reduction from 15,000 pounds responding to landlord concerns about affordability. Improvements made from October 2025 can count toward the cap, allowing landlords to spread the cost over several years.

Government estimates suggest an average upgrade cost of 6,100 to 6,800 pounds per property. Energy data firms and lettings bodies estimate higher costs for older or non-standard construction homes, which may require more extensive work.

Landlords who let homes without the required improvements, and without a valid registered exemption, face penalties of up to 30,000 pounds.

The rating system is changing too

The familiar A to G Energy Efficiency Rating, based on running cost, is being replaced by the Home Energy Model (HEM). HEM assesses fabric performance, heating system efficiency and smart readiness, measuring how well a home retains heat rather than how much it costs to heat. New HEM-based EPCs are due from late 2026, with legacy ratings valid until October 2029.

The current A to G rating is based on the estimated cost of running a home. The Home Energy Model instead measures fabric performance, including insulation, glazing and air tightness, alongside heating system efficiency and smart readiness. This shifts the focus from cost to thermal performance.

New HEM-based EPCs are due from late 2026 and will run alongside the current system. Legacy ratings stay valid until October 2029, meaning an EPC C achieved under the current system before that date is expected to remain compliant until it expires.

It is important to note that a current C rating is not automatically a HEM C. Landlords should review their position against the new metrics as band boundaries are finalised.

The royal estates example

Analysis of more than 700 domestic EPCs across the Duchies of Lancaster and Cornwall and the Sandringham estate found around 90 percent rated D or below. If representative, more than 1,000 homes could need work before 2030, a bill estimated at up to 10 million pounds. The estates cite historic and rural buildings as a challenge.

The analysis covered domestic EPCs across the three estates. At Sandringham, 99 percent of sampled lets were rated D or below. The Duchy of Lancaster saw over 90 percent at that level, while the Duchy of Cornwall had around 80 percent.

If the sample is representative, more than 1,000 homes across the estates could need upgrading before the 2030 deadline. The potential bill is estimated at up to 10 million pounds.

The estates point to the challenges of historic and rural buildings. The Duchy of Cornwall said it had spent 11 million pounds on improvements since 2022, with 50 million pounds more planned.

What landlords should do now

Order of works matters. Under HEM's fabric-first approach, insulation, draught-proofing and glazing come before expensive heating changes. Landlords should check their current EPC and its expiry, review it against the coming HEM metrics, and consider available support including the Boiler Upgrade Scheme and the Warm Homes Local Grant.

Landlords should prioritise fabric improvements such as insulation, draught-proofing and glazing before considering heating system changes. This fabric-first approach aligns with HEM's focus on how well a home retains heat.

Checking the current EPC and its expiry date is a sensible first step. A valid C from before October 2029 buys time, but should be reviewed against the coming HEM metrics as band boundaries are still being finalised.

Support is available. The Boiler Upgrade Scheme, the Warm Homes Local Grant and low-interest loans the government has said it will make available can help with costs.

Landlords with borderline or non-standard construction, such as solid wall or pre-1919 homes, should model both systems before committing to work, as HEM band boundaries are still being finalised.

Frequently asked questions

When do rental homes need to reach EPC C?

By 1 October 2030 for all privately rented homes in England and Wales, up from the current EPC E minimum, unless a valid exemption is registered.

How much can I be required to spend?

There is a cost cap of 10,000 pounds per property, with lower caps for homes worth under 100,000 pounds. Work done from October 2025 can count toward it.

Is the EPC rating system changing?

Yes. The A to G cost-based rating is being replaced by the Home Energy Model, which measures fabric performance, heating and smart readiness. New EPCs are due from late 2026.

Will my current EPC C still count?

An EPC C achieved under the current system before October 2029 is expected to remain compliant until it expires. Do not assume it will translate to a C under the new model.

What happens if I do not comply?

Letting a home below the standard without a valid exemption can bring penalties of up to 30,000 pounds. Local authorities enforce the rules using the PRS database and exemptions register.