Whole-day record · Great Britain
Greenest day on record
The record
72.8%
Beat 69.1% from 15 September 2025 by 3.8 percentage points.
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72.8%4 Oct 202520182020202220242026
RecordBest of each monthRecord broken
- Times broken
- 19
- since March 2017
- Standing for
- 12 months
- since 4 Oct 2025
- Previous record
- 69.1%
- 15 Sept 2025
- Best in 2026
- 70.4%
- 10 Oct 2026
The record for greenest day is 72.8%, over the whole day on Saturday 4 October 2025. It beat the record of 69.1%, set on 15 September 2025, by 3.8 percentage points.
Since March 2017, the record has been broken 19 times.
The best value in 2017 was 39.7%. The record is 33.1 percentage points higher.
4 of the ten best days were in the past twelve months.
So far in 2026, the best value is 70.4%, on 10 October 2026. That is 97% of the record.
History
Every time the record was broken
Newest first. Choose a day to see its charts. Rows in grey are from the first year of the data.
| Day | Record | Rise | Held for |
|---|---|---|---|
| 4 October 2025 | 72.8% | +3.8 points | Stands · 12 months |
| 15 September 2025 | 69.1% | +0.9 points | 19 days |
| 25 May 2025 | 68.1% | +0.4 points | 4 months |
| 7 April 2024 | 67.7% | +2.1 points | 14 months |
| 23 March 2024 | 65.6% | +1.3 points | 15 days |
| 24 December 2023 | 64.3% | +0.1 points | 3 months |
| 15 July 2023 | 64.2% | +2.0 points | 5 months |
| 1 October 2022 | 62.2% | +1.6 points | 9 months |
| 5 July 2020 | 60.5% | +0.4 points | 2 years and 3 months |
| 5 April 2020 | 60.1% | +5.6 points | 3 months |
| 22 February 2020 | 54.5% | +0.6 points | 43 days |
| 17 August 2019 | 53.9% | +4.6 points | 6 months |
| 30 June 2019 | 49.3% | +3.5 points | 48 days |
| 13 January 2019 | 45.8% | +0.0 points | 6 months |
| 21 September 2018 | 45.8% | +2.8 points | 4 months |
| 14 June 2018 | 43.0% | +2.9 points | 3 months |
| 17 March 2018 | 40.1% | +0.4 points | 3 months |
| 2 October 2017 | 39.7% | +0.9 points | 5 months |
| 30 April 2017 | 38.9% | +0.1 points | 5 months |
| 25 December 2016 | 38.8% | +4.1 points | 4 months |
| 24 December 2016 | 34.7% | +0.2 points | 1 day |
| 7 August 2016 | 34.5% | +3.1 points | 5 months |
| 27 March 2016 | 31.4% | +1.4 points | 4 months |
| 26 March 2016 | 30.0% | +7.4 points | 1 day |
| 25 March 2016 | 22.6% | +7.8 points | 1 day |
| 24 March 2016 | 14.8% | +1.2 points | 1 day |
| 14 March 2016 | 13.6% | +2.4 points | 10 days |
| 12 March 2016 | 11.2% | +1.4 points | 2 days |
| 11 March 2016 | 9.8% | +4.4 points | 1 day |
| 10 March 2016 | 5.4% | — | 1 day |
The 11 grey rows are from the first year of the data, when each new day could set a record.