England and Wales
Since 1 April 2018, it is illegal to let out any residential property in England and Wales with an EPC rating of band F or G (the least efficient bands).
Since 1 April 2020, it is illegal to continue letting out residential property that doesn't have an EPC rating of band E or higher. This means that from 1 April 2020 all residential property let out to tenants must have an EPC rating of band E or higher, even if the tenancy started before this date.
The required ratings are subject to exemptions.
For commercial property, when new tenancies are created a property must currently have an EPC rating of band E or higher. From 1 April 2023, this minimum will apply to all commercial tenancies, new and existing. The minimum will continue to rise gradually until, by 1 April 2030, properties will need to have a minimum EPC rating of band B.
The band E standard required in Scotland was removed due to challenges facing the residential private rented sector during the Coronavirus (COVID-19) pandemic. Amended plans require that properties have a band C rating as a minimum by 2025, where this is technically feasible and cost-effective. The requirement will apply regardless of technical feasibility and cost-effectiveness from 2028.
In Scotland, the EPC must be displayed somewhere within the property (eg in the meter cupboard or next to the boiler).
For further information read Minimum Energy Efficiency Standards for residential properties.