CM23 postcode area guide — East Hertfordshire

Where is CM23?

Broadband & internet speeds in CM23

Strong coverage

Broadband availability in the CM23 postcode district (East Hertfordshire) is Strong — superfast is near-universal and gigabit is rolling out. Across the 1,076 postcodes Ofcom measures in CM23, superfast broadband (30 Mbit/s or faster) reaches 95.2% of premises and gigabit-capable lines are available to 72.2%.

Around 0.1% of premises in CM23 fall below the Universal Service Obligation (a minimum of 10 Mbit/s download and 1 Mbit/s upload), so the overwhelming majority of homes and businesses here can already order a decent fixed line. For a business that depends on its connection, the figures that matter most are gigabit and full-fibre availability — the symmetric, low-contention services we quote leased lines and FTTP against.

Sample postcodes in CM23

Run a speed test to see what you're actually getting, or check your exact postcode.

Mobile signal around East Hertfordshire

Ofcom's coverage model for the wider East Hertfordshire district (71,670 premises):

Signal varies street by street — use the mobile coverage checker to compare EE, O2, Three and Vodafone at an exact postcode.

Crime in CM23

Police recorded 253 incidents within about a mile of the centre of CM23 in May 2026 (latest published street-level data). The breakdown:

Raw counts favour busy town centres — a high street with shops and nightlife records more incidents than a residential cul-de-sac. Source: police.uk open data (point sample around the district centroid).

House prices in CM23

Based on 479 sales registered with HM Land Registry in the last 12 months, the median sold price in CM23 is £425,000, down 1.2% on the previous year (£429,995).

Latest recorded sales in CM23

Contains HM Land Registry data © Crown copyright and database right 2026, licensed under the Open Government Licence v3.0.

Who lives here? East Hertfordshire demographics

Census 2021 figures for the wider East Hertfordshire district (150,155 residents, 62,023 households):

Source: ONS Census 2021 (district level — the finest openly licensed cut we republish). © Crown copyright, OGL v3.0.

Schools in and around CM23

Source: DfE Get Information about Schools (England & Wales). Check Ofsted report cards for inspection detail — headline one-word grades were retired in 2024.

Food hygiene ratings in CM23

309 rated food businesses operate in CM23. 224 hold the top rating of 5, 30 are rated 4, and 5 are rated 2 or below.

Among the 5-rated: +AJ's Culinary Creations Ltd, Abbeyfield House, Ace Of Lanes, Afonso's Cafe, Albert's.

Source: Food Standards Agency, food hygiene ratings (FHRS) open data.

Energy performance (EPC) in CM23

From a sample of 173 Energy Performance Certificates across 9 CM23 postcodes, the most common rating is band D (average band C). 47% of sampled homes are rated C or better.

Source: MHCLG Energy Performance of Buildings Data (England & Wales), sampled at postcode level and refreshed monthly. Individual certificates are on each postcode’s page.

Phone area codes for East Hertfordshire

Landlines around CM23 typically use:

Had a call from an unknown number? Use our free UK phone number checker to see who called.

What's it like living in CM23?

Postcodes in CM23

Neighbouring districts

All Chelmsford (CM) postcode districts ›

Frequently asked questions

Sources: HM Land Registry Price Paid Data, police.uk street-level crime, Ofcom Connected Nations, ONS Census 2021, DfE Get Information about Schools, Food Standards Agency FHRS — all © Crown copyright, licensed under the Open Government Licence v3.0. Figures are area aggregates; individual addresses vary. Energy performance (EPC) data will be added when our Open Data Communities registration is approved.