Government published the Carbon Budget Delivery Plan

The Carbon Budget Delivery Plan was published by the Department for Energy Security and Net Zero on 30 March 2023, under the 2022 to 2024 Sunak Conservative government¹. It was presented to Parliament under section 14 of the Climate Change Act 2008 and ordered by the House of Commons to be printed on the same date¹. The department said the plan was "being published to inform Parliament and the public on the government's proposals and policies to enable carbon budgets to be met"¹.

The plan covers carbon budgets four, five and six, spanning 2023 to 2037¹. Carbon budgets are a statutory cap on the total greenhouse gas emissions the UK can emit in a five-year period². The fourth budget, covering 2023 to 2027, has a cap of 1,950 million tonnes of carbon dioxide equivalent (MtCO2e), a 52% reduction on 1990 levels; the fifth, covering 2028 to 2032, has a cap of 1,725 MtCO2e, a 58% reduction; and the sixth, covering 2033 to 2037, has a cap of 965 MtCO2e, a 77% reduction². The plan states that the UK is "legally required to reduce greenhouse gas emissions by at least 100% by 2050 on 1990 levels"¹.

The department's own projections, set out in the plan, show expected performance against each budget. A positive figure indicates emissions reduced beyond the level required; a negative figure indicates further savings are needed¹.

The plan states that, after baseline adjustments, CB4 could already be met with 7Mt per year of headroom, while the savings required from further proposals and policies to meet CB5 and CB6 are 9Mt per year and 199Mt per year respectively¹. It records that between 1990 and 2021, UK emissions fell by 48% while the economy grew by 65%¹. The plan also notes that the carbon budgets apply to the whole of the UK economy and society, and that devolved administrations were consulted¹.

"This Carbon Budget Delivery Plan provides the detail, setting out the current package of proposals and policies prepared by the Secretary of State (as of March 2023) to enable the delivery of Carbon Budgets 4, 5 and 6."

The plan followed a July 2022 High Court judgment that the 2021 Net Zero Strategy was unlawful under the Climate Change Act 2008, with the court ruling that the government should set out more detail on how it aims to meet its carbon budgets and reach net zero². The March 2023 plan updated the policies and commitments in that strategy². A second legal challenge in May 2024 found the Carbon Budget Delivery Plan itself unlawful in its assertion that the plans put forward would enable the UK to meet its carbon budgets, and ruled that a revised plan was needed by 2 May 2025².

Why it matters for households

Carbon budgets set the legal ceiling on UK emissions and therefore shape the policies that reach into homes: how electricity is generated, how homes are heated, and what is expected of buildings over the 2020s and 2030s. The plan's own projections show the sixth carbon budget, covering 2033 to 2037, falling short by 6MtCO2e per year on the figures published, meaning further savings would be required¹. For a household, the practical consequence is that the direction of policy set out in the plan, and the pace at which it is delivered, bear on the cost and availability of low-carbon heating and electricity, and on how exposed a home remains to volatile fossil fuel prices. The Climate Change Committee later said the government "is not moving fast enough to reduce greenhouse gas emissions and protect households and businesses from volatile fossil fuel prices"². The plan itself acknowledges that the package of proposals and policies "will evolve to adapt to changing circumstances" and that there is "considerable fluidity in the final delivery"¹.

What happens next

The Carbon Budget Delivery Plan was superseded as the government's strategy document by the Carbon Budget and Growth Delivery Plan, published on 29 October 2025, which sets out how the government would meet the emissions reductions for carbon budgets four to six². The government has said it will publish a new delivery plan setting out plans to achieve the reductions required for the seventh carbon budget, which was agreed in both Houses in 2026 and commits the UK to emissions reductions of 87% from 1990 levels by 2042². The government has not yet responded to the Climate Change Committee's June 2026 progress report².

Sources2 cited

1. Carbon Budget Delivery Plan - GOV.UK, gov.uk
2. [](https://researchbriefings.files.parliament.uk/documents/CBP-9888/CBP-9888.pdf), researchbriefings.files.parliament.uk