Total Crime Rate
74.1 per 1,000
All offences · May 2025 - Apr 2026Violent Crime Rate
26.5 per 1,000
May 2025 - Apr 2026Trem Y Dyffryn area has the 12th lowest crime rate of 23 local areas in Mountain Ash , and the 340th highest crime rate of 791 local areas in Rhondda Cynon Taf .
This postcode forms a relatively safe pocket compared with the surrounding streets. Neighbouring areas record much higher crime levels, even though this postcode itself remains comparatively low-crime.
The overall crime rate in the area around Trem Y Dyffryn (CF45 4AQ) in the last 12 months was 74.1 per 1,000 residents and was 19.5% lower than the Mountain Ash average (92.1 per 1,000 residents). In the last 12 months, this area’s most reported crimes were Violence and sexual offences with 10 offences recorded. The least common crime was Other crime with 1 case , unchanged from 2025. The fastest-growing crime category was Anti-social behaviour ( 100.0% YoY). The sharpest decline was Violence and sexual offences ( -37.5% YoY).
Violent crimes totalled 10 (≈ 26.5 per 1,000 residents). Year-over-year these were falling ( -37.5% ). Over the last decade, overall crime has falling ( -68.2% comparing early vs recent averages) .
In the area around Trem Y Dyffryn (CF45 4AQ), the main crime hotspot is near Union Street. Police recorded 15 crimes here, including 6 violent or public-order offences. All these locations are within roughly 0.3 miles.
View Crime In Mountain Ash| Month | Crime | Location* | Last Outcome |
|---|---|---|---|
| Apr 2026 | Other crime | Woodland Terrace | Investigation complete; no suspect identified |
| Apr 2026 | Criminal damage and arson | Aber-Ffrwd Road | Unable to prosecute suspect |
| Apr 2026 | Anti-social behaviour | Parking Area | — |
| Apr 2026 | Violence and sexual offences | Graig Street | Under investigation |
StreetScan crime figures are based on official UK open data:
Contains public sector information licensed under the Open Government Licence v3.0. © Crown copyright and database right.