BT27 broadband and area guide
Ofcom coverage, connection speeds, house prices and local data for 570 postcodes across 3 sectors in Lisburn and Castlereagh.
Full fibre
0%
Gigabit
95%
Superfast
99%
Postcodes
570
BT27 spans 570 postcodes in Lisburn and Castlereagh with 99.1% superfast coverage and 95.3% gigabit, representing the highest superfast penetration in this batch.
Broadband speeds in BT27
Share of BT27 premises by the fastest download speed available, averaged across all 570 postcodes in the district.
This district shows remarkable clean coverage. Superfast reaches 99.1%, almost universal. Gigabit at 95.3% reflects cable infrastructure serving the overwhelming majority. Critically, there are zero postcodes below the Universal Service Obligation threshold of 30 Mbps. Only 0.1% fall below 10 Mbps, a single postcode in 570. The speed split is heavily skewed upwards, with 95.3% gigabit, 3.8% superfast, and 0.1% below 10 Mbps, leaving no middle ground. When superfast is nearly universal, coverage gaps are genuinely rare. This combination of near-total superfast reach and very high gigabit penetration means BT27 residents are virtually certain to access modern broadband.
Source: Ofcom Connected Nations. Percentages are district-wide averages of postcode-level availability, so rows may not sum to exactly 100%.
Connectivity in detail
Below 10 Mbps USO
0%
Premises unable to get the 10 Mbps universal service minimum
Fixed wireless
0%
Premises that can use a fixed wireless access service
Broadband by sector
BT27 splits into 3 postcode sectors. Coverage and prices can differ street by street, so open a sector below to find your exact postcode.
| Sector | Postcodes | Superfast | Full fibre | Gigabit |
|---|---|---|---|---|
| BT27 4 | 234 | 99% | 0% | 94% |
| BT27 5 | 284 | 99% | 0% | 96% |
| BT27 6 | 52 | 97% | 0% | 95% |
All BT27 4 postcodes (234)
All BT27 5 postcodes (284)
All BT27 6 postcodes (52)
Best deals
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Living in Lisburn and Castlereagh
Homes in BT27 are virtually assured of modern broadband. The infrastructure is mature and thorough. Connectivity is not a decision factor here; it's assumed.
Remote worker score
55/100
Connectivity and amenities for home working
Family score
50/100
Schools, safety and family amenities
Value score
50/100
What you get for the local price level
BT27 broadband FAQs
Why is superfast (99.1%) nearly higher than gigabit (95.3%)?
Superfast includes the gigabit tier plus additional postcodes on non-cable networks. The 3.8% gap has alternative providers delivering 30-300 Mbps.
Is there even one postcode below 30 Mbps?
No. Every postcode in BT27 meets the Universal Service Obligation minimum. This is exceptionally rare.
What about the 0.1% below 10 Mbps?
That single postcode (of ~570) likely represents a data boundary case or newly built area not yet fully networked.
Can I safely ignore broadband when house hunting here?
Yes. BT27's coverage is so universal that broadband availability is not a risk factor for any property in the district.
Neighbouring districts
Check your exact postcode
Every postcode in BT27 has its own page with broadband speeds, house prices, school ratings and crime stats. You can also compare providers for your address.
Data sources: Broadband data from Ofcom Connected Nations 2025 · House prices from HM Land Registry · Crime from Police.uk · See all data sources