19 providers offer 289 broadband deals in Marconi, from £13.50 a month (£18 after 12 months) and up to 5,000 Mbps. Typical measured speed is 113 Mbps down and 25 Mbps up, 12% above the UK download average. Full fibre is available to 92.3% of homes.
Deals for Marconi (CM1), checked and refreshed daily.
Best value broadband deal in Marconi (CM1)
The best value in Marconi (CM1) on full first-year cost is 4th Utility's 250Mb Full Fibre CityFibre (24 Months): £198 across year one, about £17 a month. 250 Mbps covers streaming, video calls and working from home.
Best value in Marconi (CM1)
250Mb Full Fibre CityFibre (24 Months)
£16.50/mo
for 12 months, then £22/mo
Cheapest broadband deal in Marconi (CM1)
The cheapest deal in Marconi (CM1) is 150Mb Full Fibre CityFibre (24 Months) from 4th Utility at £13.50 a month for 150 Mbps. It's full fibre, so the advertised speed is the speed that reaches the router. The £13.50 is an intro price that rises to £18.00 a month after the intro window, making the real first-year cost £162. Above the UK average on download.
Cheapest in Marconi (CM1)
150Mb Full Fibre CityFibre (24 Months)
£13.50/mo
for 12 months, then £18/mo
Fastest broadband deal in Marconi (CM1)
The fastest deal available in Marconi (CM1) is Full Fibre 5 Gigafast+ from Sky at 5,000 Mbps.
Fastest in Marconi (CM1)
£50/mo
No rises, no surprises.
Compare broadband deals in Marconi (CM1)
£22.99/mo
rises to £26.99 in March 2027 (+£4)
£19/mo
No rises, no surprises.
150Mb Full Fibre CityFibre (24 Months)
£18.50/mo
for 12 months, then £23.50/mo
£25.99/mo
rises to £29.99 in March 2027 (+£4)
Broadband providers in Marconi (CM1)
19 providers serve Marconi (CM1) including Virgin Media, BT and Vodafone, with Sky the fastest at 5,000 Mbps.
Ranked by Ofcom complaints per 100,000 customers, fewest first. A down arrow is below the industry average, up is above, and a dash means Ofcom publishes no figure for that provider (usually because it is below Ofcom's 1.5% market-share reporting threshold). A small diagonal arrow shows the past-year trend (↘ improving, ↗ getting worse).
Ofcom records the typical Marconi (CM1) download speed at 113 Mbps.
Upgrade nudge
Room to upgrade in Marconi (CM1)
Only 17% of the 22,000 connections here are on 300Mbps or faster, even though 92% can get gigabit.
The faster line is already there. For most of these homes it is the contract holding them back, not the infrastructure.
Is your broadband good enough?
The typical Marconi (CM1) line runs 113 Mbps.
Working from home
OKStreaming and family use
GoodWhat speeds are people actually getting?
Gigabit reaches 92% of Marconi (CM1), and the fastest available is 1,000 Mbps. The full split by band is below.
What broadband coverage does Marconi (CM1) have?
Superfast broadband reaches 97% of Marconi (CM1) premises and gigabit 92%, on Ofcom's premise-level data.
Can I rely on mobile broadband in Marconi (CM1)?
Outdoor 5G reaches 100% of Marconi (CM1) homes. Here is how mobile holds up if the line drops.
The two 5G figures differ. “5G availability” is everyday 5G running on the existing 4G core, which is what most phones show. “Next-gen 5G” is standalone 5G: a full 5G network with lower lag, still reaching fewer places.
5G & 4G home broadband
Outdoor 5G covers 100% of Marconi (CM1), enough for a 5G home-broadband hub to stand in for a fixed line.
How Marconi (CM1) compares within Chelmsford
Across 3 postcode districts in Chelmsford, by connection count, typical speed and gigabit coverage.
Nearby areas
Frequently asked questions
Ready to switch
See what's actually live in Marconi (CM1).
Enter your address and we'll show every deal you can genuinely order on your line, ranked by what you'll pay across the whole contract, not by who pays us.
Speed and coverage figures for Marconi (CM1)come from Ofcom's Connected Nations data, current to January 2026. Deal prices are pulled live from providers. Compiled by the FindBroadband team. See how we rank and source our data.