National Cyber Security Centre

Nationally (UK) significant incidents represented 48% (204) of all incidents between September 2024 and August 2025, a significant increase from last year (89).

There were 62 nationally (UK) significant incidents reported between September 2022 and August 2023, 4 of which were categorised as highly significant in nature.

There were 63 nationally (UK) significant incidents reported between September 2021 and August 2022, 1 of which were categorised as highly significant in nature.

Among this year's nationally significant incidents in the UK, 4% (18) were categorised as highly significant in nature.