15 providers offer 184 broadband deals in St Mary's, from £20.00 a month and up to 1,600 Mbps. Typical measured speed is 56 Mbps down and 14 Mbps up, 45% below the UK download average.
Best value broadband deal in St Mary's, Isles of Scilly (TR21)
The best value in St Mary's, Isles of Scilly (TR21) on full first-year cost is Plusnet's Full Fibre 145: £292 across year one, about £24 a month. A £155 reward card is bundled in. 145 Mbps covers streaming, video calls and working from home.
Best value in St Mary's, Isles of Scilly (TR21)
£22.99/mo
rises to £26.99 in March 2027 (+£4)
Avg £26.32/mo over contract · £632 total over 24 months
Fastest broadband deal in St Mary's, Isles of Scilly (TR21)
The fastest deal available in St Mary's, Isles of Scilly (TR21) is Full Fibre 1.6GB Premium from EE at 1,600 Mbps.
Fastest in St Mary's, Isles of Scilly (TR21)
Full Fibre 1.6GB Premium
115 Mbps upload · Full Fibre
Best for power users & big households
£33.99/mo
rises to £37.99 in March 2027 (+£4)
Avg £37.32/mo over contract · £896 total over 24 months
Cheapest broadband deal in St Mary's, Isles of Scilly (TR21)
The cheapest deal in St Mary's, Isles of Scilly (TR21) is 300Mb Full Fibre (24 Months) from 4th Utility at £20.00 a month for 300 Mbps. It's full fibre, so the advertised speed is the speed that reaches the router. The £20.00 is an intro price that rises to £40.00 a month after the intro window, making the real first-year cost £240. Onestream is essentially level at £20.63 a month.
Cheapest in St Mary's, Isles of Scilly (TR21)
300Mb Full Fibre (24 Months)
300 Mbps upload · Full Fibre
Best for 4–5 person households, heavy use
£20/mo
for 12 months, then £40/mo
Avg £30/mo over contract · £720 total over 24 months
Runner-up on price
Onestream Fibre 55
10 Mbps upload · Hybrid Fibre
Best for small homes, single 4K streamer
£19.94/mo
rises to £22.69 in April 2027 (+£2.75)
Avg £22/mo over contract · £528 total over 24 months
Compare broadband deals in St Mary's, Isles of Scilly (TR21)
£21/mo
rises to £24 in April 2027 (+£3)
Avg £23.25/mo over contract · £558 total over 24 months
£30/mo
rises to £33.50 in April 2027 (+£3.50)
Avg £32.63/mo over contract · £783 total over 24 months
Sky Full Fibre Gigafast
100 Mbps upload · Full Fibre
Best for power users & big households
£31/mo
No rises, no surprises.
£749 total over 24 months
Onestream Fibre 55
10 Mbps upload · Hybrid Fibre
Best for small homes, single 4K streamer
£19.94/mo
rises to £22.69 in April 2027 (+£2.75)
Avg £22/mo over contract · £528 total over 24 months
Broadband providers in St Mary's, Isles of Scilly (TR21)
15 providers serve St Mary's, Isles of Scilly (TR21), with EE the fastest at 1,600 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 St Mary's, Isles of Scilly (TR21) download speed at 56 Mbps.
Upgrade nudge
Room to upgrade in St Mary's, Isles of Scilly (TR21)
Only 0% are on 300Mbps or faster, even though 61% 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 St Mary's, Isles of Scilly (TR21) line runs 56 Mbps.
Working from home
OKStreaming and family use
OKWhat speeds are people actually getting?
Gigabit reaches 61% of St Mary's, Isles of Scilly (TR21), and the fastest available is 1,000 Mbps. The full split by band is below.
Which broadband networks reach St Mary's, Isles of Scilly (TR21)?
The wholesale networks carrying St Mary's, Isles of Scilly (TR21) broadband, from Openreach to Virgin Media and the altnets, read off the live deals.
Altnets present in St Mary's, Isles of Scilly (TR21), derived from who is actually selling into addresses here. Worth checking your specific address because their footprints can stop and start a few doors apart.
- CityFibre: Sky, The One Broadband, Vodafone
- 4th Utility: 4th Utility, Rise Fibre
Layered on top, Openreach also reach this area (Openreach has a nationwide footprint, so it'll be available).
Across the area, 15 providers are listing live deals.
What broadband coverage does St Mary's, Isles of Scilly (TR21) have?
Superfast broadband reaches 96% of St Mary's, Isles of Scilly (TR21) premises but gigabit only 61%, so around 35% of homes can get fast broadband but not the fastest.
How St Mary's, Isles of Scilly (TR21) compares within Isles of Scilly
Across 5 postcode districts in Isles of Scilly, by premises count, typical speed and gigabit coverage.
Nearby areas
Frequently asked questions
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* Based on Go.Compare research estimating that 28% of UK broadband users pay for faster broadband speeds than they need (which we interpret as overpaying), equivalent to around 7.5m UK households.
Speed and coverage figures for St Mary's, Isles of Scilly (TR21)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.