HA4 postcode district: Hillingdon and around
HA4 is a postcode district in England, with 1,137 postcodes in use in 6 sectors. It has postcodes in Hillingdon and Harrow. It is split between 2 councils: Hillingdon (1,133 postcodes) and Harrow (4).
- Postcodes in use
- 1,137
- Sectors
- 6
- Councils
- 2 councils
- Places
- 2 places
Source: ONS Postcode Directory, August 2026, loaded 20 October 2026.
Every postcode in HA4, by gigabit broadband
- No home or business can get gigabit: 52
- Some can get gigabit: 104
- Every home and business can get gigabit: 957
- Ofcom gives no figure: 24
- Outline: where 5 or more postcodes without gigabit lie together
Of the 1,137 postcodes in HA4 that ONS places, 52 have no home or business that can get gigabit, 104 have some that can, 957 can all get it and 24 have no Ofcom figure.
Each mark is a postcode's centre point as ONS gives it, not a building. Press one to see its postcode and open its page. A dashed outline shows where 5 or more lie within 150 metres of each other. It is not a boundary, and no boundary is drawn. Where marks overlap, the one first in the key is drawn; the counts include every postcode. Names in italics are council wards: we hold no town or village names here.
The middle of its postcodes: latitude 51.5703, longitude -0.4107. Open this area on OpenStreetMap
Sources: ONS Postcode Directory, August 2026, loaded 20 October 2026; Ofcom Connected Nations, Connected Nations, Spring 2026; roads, rivers and built-up areas: Ordnance Survey open maps. Contains OS data © Crown copyright and database right 2026. Drawn by us. Street map: Ordnance Survey, OS Open Zoomstack, Open Government Licence v3.0, drawn with MapLibre.
Postcodes without gigabit
52 postcodes here have no gigabit. These are the 12 first in postcode order.
Where the postcodes without gigabit lie together
- 8 postcodes without gigabit, outlined on the map. HA4 7GD, is the one nearest the middle of them.
What broadband can you get in HA4?
Ofcom reports on 1,113 of the 1,137 postcodes in HA4. At 957 of them every home and business can get gigabit broadband.
Ofcom gives each postcode's share of homes and businesses, not how many there are, so these count postcodes. Each postcode page has its own figures. A provider's checker answers for one address.
Check one address on Ofcom's checkerSource: Ofcom Connected Nations, Connected Nations, Spring 2026, data for January 2026.
Is HA4 at risk of flooding?
153 of the 1,137 postcodes in HA4 have a home or business in an area at risk of flooding from rivers or the sea, the Environment Agency says. At those, it puts 762 homes and businesses in an area at high or medium risk.
High: 3.3% or more a year (1 in 30). Medium: 1% to 3.3% a year. Low: 0.1% to 1% a year. Very low: under 0.1% a year (1 in 1,000). Each band is the chance of flooding in any one year.
Homes and businesses in an area at risk of flooding from rivers or the sea, as the Environment Agency counts them, added up over the postcodes. It is for the land, not each building, and leaves out surface water, groundwater and sewers. Each postcode page has its own figures and its flood warning areas.
Source: Environment Agency flood risk, published 6 July 2026.
What do homes sell for in HA4?
Homes in HA4 sold for a typical £565,000 in the 12 months to September 2026, across 446 sales, HM Land Registry's figures show. The 12 months before gave £577,500 from 641 sales: not a change larger than chance would explain, given which homes happened to sell.
- Detached £832,500 66 sales
- Semi-detached £645,000 148 sales
- Terraced £548,000 121 sales
- Flat or maisonette £330,000 111 sales
Each bar is that kind's typical price, against the most expensive kind here.
Standard sales of homes at market value. A typical price is the median, the middle sale. Sales take weeks to be registered, so the last month or two are incomplete. Each postcode page gives the figure for its own postcode sector.
Source: HM Land Registry Price Paid Data, files dated 28 October 2026.
Postcodes in HA4
Pick a sector, then a postcode. A sector is the district plus the next digit.
Places in HA4
Towns and villages with postcodes in HA4, and how many each has here.
Who covers HA4
How many of the district's postcodes in use fall under each council, constituency and police force area.
Councils
- Hillingdon1,133
- Harrow4
Constituencies
- Ruislip, Northwood and Pinner610
- Uxbridge and South Ruislip523
- Harrow West4
Police force areas
- Metropolitan Police1,137
Next to HA4
"Next to" is by number: the districts before and after HA4 in the HA area.
Check a postcode
Where the facts on this page come from
- Office for National Statistics: ONS Postcode Directory
- Ofcom Connected Nations
- Environment Agency flood risk
- HM Land Registry Price Paid Data
Contains public sector information licensed under the Open Government Licence v3.0. Contains HM Land Registry data © Crown copyright and database right 2021. This data is licensed under the Open Government Licence v3.0.
Licence: Open Government Licence v3.0.
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