Two new studies cited by Letting Agent Today (March 2026) have confirmed what many buy-to-let (BTL) landlords already suspect: the race to upgrade rental properties to meet EPC C standards by October 2030 will be costly, regionally uneven, and could push thousands of properties out of the market. For tenants, that means tighter rental availability. For landlords, it means planning starts now.

The costs are real, and they vary wildly

Energy Performance Certificate (EPC) ratings measure how efficiently a property uses energy. The government's Warm Homes Plan requires all private rental properties in England to reach a minimum of EPC C by 2030. Properties currently rated D or below will need substantial work.

The numbers matter. According to analysis cited by Letting Agent Today (March 2026), average upgrade costs range from £5,400 to £7,633 per property, with a proposed government spending cap of up to £10,000. But those figures mask regional reality. In areas like Powys (Wales), where 83% of rental stock sits below the EPC C target, average upgrade costs hit £10,759 - a figure that dwarfs annual rental income of £7,248. That's a cost-to-income ratio of 148%. In other words, landlords there would be spending nearly one and a half years' annual rent to comply.

Improvements required typically include wall insulation, upgraded heating systems, double glazing, or renewable energy installations. For older properties - which make up a significant portion of the rental stock - these aren't cosmetic upgrades. They're structural.

Who exits the market first?

Jason Harris-Cohen, Managing Director at LandlordBuyer, warned that "many owners, particularly those with older homes, face substantial costs that may simply not be financially viable." What that translates to in practice: landlords will sell. Properties will be converted to owner-occupation. Rental supply tightens.

This matters for your tenants. It's already harder to find rental accommodation in many areas - void periods are stretching longer, and competition for quality rentals is fierce. A mass landlord exodus would make that worse. Your tenants will feel the pressure.

But it also cuts both ways. Some landlords might pass costs forward through rent increases or take longer to achieve compliance, catching properties between ratings. Tenants in sub-C properties should expect conversations about upgrades and timelines. Those in sub-D properties should prepare for potential landlord decisions about the future of the property.

What you should do now

The October 2030 deadline is still nearly four years away, but the market won't wait. Capital costs concentrate. Surveyor availability tightens. Supply chains for installation get bottlenecked. The landlords who plan early will pay less and avoid the rush.

If you don't have a recent EPC survey, you may wish to commission one - knowing your current rating and the gap to EPC C is the starting point for any planning. You may also wish to speak to a qualified surveyor about realistic costs for your property type and location before committing to a timeline. And it's worth a conversation with your mortgage lender or broker about whether the investment pencils out given compliance costs - some lenders are adjusting criteria for rental properties with EPC risk.

For those holding multiple properties, the highest-risk combination is older stock in lower-income rural areas. Those properties face the worst cost-to-income ratios. Urban portfolios tend to have lower upgrade costs per property, so the maths is often more favourable there.