The police recorded 93.9 crimes per 1,000 people a year in Llangefni from September 2023 to August 2026, 23% higher than the typical town's 76.2. The most common was violence and sexual offences, at 53.0. In the 12 months to August 2026 it was 98.5, up from 84.5 in the 12 months to August 2024.