Wales has written a new five‑year carbon limit into law. After a Senedd vote on 2 December 2025, the Climate Change (Carbon Budget) (Wales) Regulations 2025 fix the Fourth Carbon Budget (2031–2035) at an average 73% below the statutory baseline. The regulations take effect on 5 December 2025.

That “baseline” is defined in the Environment (Wales) Act 2016 as Wales’s aggregate net greenhouse gas emissions in 1990 for carbon dioxide, methane and nitrous oxide, and 1995 for fluorinated gases. Wales’s targets and budgets also include its share of international aviation and shipping.

The Climate Change Committee (CCC) advised ministers in May that a 73% average cut for 2031–35 is deliverable and aligns with the path to net zero by 2050. Its analysis indicates this level equates to roughly 58% below 2022 emissions and can be achieved largely through electrified heat, cleaner transport and better‑insulated homes, at an average system cost of around £390 million per year to 2050 (about 0.4% of GDP).

The new budget sits on a stepped pathway already in law: Carbon Budget 2 (2021–2025) at an average 37% below baseline and Carbon Budget 3 (2026–2030) at 58% below baseline. Together, these milestones create a clear glide path towards the 2040 target of an 89% cut and net zero by 2050.

Alongside setting the 2031–35 limit, ministers confirmed they will hold to a 0% use of international carbon credits for 2026–2030, meaning the current budget must be met through action inside Wales-keeping investment and co‑benefits local. The Senedd endorsed this approach on 2 December.

For rural Wales, the timing matters. Agriculture regulations passed on the same day clear the way to launch the Sustainable Farming Scheme in January 2026, rewarding nature‑positive practices that cut emissions while supporting farm incomes.

What changes on the ground? The CCC’s priority actions focus on practical shifts already underway: scaling up home insulation and low‑carbon heating, expanding public EV charging so more drivers can switch with confidence, and accelerating land‑use measures that store more carbon. These steps also mean warmer homes and cleaner air.

Progress to date shows the direction of travel. Wales’s emissions in 2022 were 35.7 MtCO2e-about 37% below 1990 levels-with over half of the fall since 2016. The new budget asks Wales to keep that pace through the early 2030s.

Accountability is built into the framework. Under the 2016 Act, ministers must publish a detailed plan for each budget period and report against it; the Government has already signalled an updated delivery plan for 2026–2030 will be published before the end of 2026. That keeps scrutiny live for communities and businesses tracking progress.

For Eco Current readers, the takeaway is pragmatic optimism. Wales now has a legally locked 73% average cut for 2031–35, backed by independent advice and a track record of improvements. The big wins-electrified heat, efficient buildings, cleaner transport and nature‑led farming-are solutions within reach that can lower bills and improve everyday life while cutting emissions.