History of UK Energy Bills
Last updated:
Pre-1990: nationalised utilities
Before 1990, electricity and gas were supplied by state-owned regional boards. Pricing was set centrally with limited regional variation; customers had no choice of supplier. The Electricity Act 1989 and the privatisation of British Gas in 1986 began the transition to a competitive retail market.
1990s liberalisation
Through the 1990s, UK domestic gas and electricity markets opened to competition. By 1999, all domestic customers could switch supplier. The wholesale-retail separation introduced cost transparency, but also created the conditions for price-volatility transmission from wholesale markets into household bills.
2000s competition era
From 2000 to 2018, the UK retail energy market operated without retail price regulation. Six "Big Six" suppliers (British Gas, EDF, E.ON, npower, Scottish Power, SSE) dominated, with smaller challengers growing after 2010. This extract does not publish a switching-rate series, so this page does not quote an annual switching percentage.
2017 Competition and Markets Authority report
The CMA's 2016 retail-energy investigation concluded that consumers on standard variable tariffs were overpaying by approximately £1.4 billion per year vs the most-competitive available deals. The report recommended a temporary price cap, ultimately enacted as the Domestic Gas and Electricity (Tariff Cap) Act 2018.
2019 default tariff price cap
The Ofgem default tariff cap came into force 1 January 2019. The cap was set quarterly, applied to all customers on standard variable tariffs (SVTs), and was reset based on a formula incorporating wholesale costs, network costs, and supplier margins. The first stored period, January – March 2019, is £1,137 for a typical dual-fuel household.
2021-2022 wholesale gas crisis
Starting summer 2021, wholesale gas prices surged. The Ofgem cap, designed for stable conditions, reset to record levels - £4,279 in January – March 2023. The government's Energy Price Guarantee sat alongside that cap that winter; this extract records the Ofgem series, not the subsidy scheme.
Supplier failures and SoLR
Ofgem's Supplier of Last Resort process moved customers of failed retailers onto surviving suppliers. Standing charges later carried a socialised recovery of those costs. This extract records the standing-charge series; it does not publish a SoLR-cost total or a failed-supplier count, so those figures are not quoted here.
2024 standing-charge consultation
In response to the post-crisis standing-charge structure, Ofgem opened a formal consultation in 2024 on reforming the standing charge. This extract does not carry a later implementation decision, so this page does not quote one.
Sources
Every figure on PlainEnergyBills is rendered directly from Ofgem source data, no number is typed in by an editor. Historical narrative cites named Acts and Ofgem publications; live cap levels live on trends and statistics pages. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.