# Castle B4 North Belfast. 492 people (mid-2024 estimate) in 0.1 square kilometres. Castle B4 had 525 usual residents at the census (NISRA Census 2021). Neighbourhood. Code N20000793. In: [Northern Ireland](https://openindex.co.uk/northern-ireland) › [Belfast](https://openindex.co.uk/belfast) ## Key figures - **Population: 525** (2021). Castle B4 had 525 usual residents at the census (NISRA Census 2021). Joint 3,005th least populated of 46,844. Source: Census 2021, England and Wales and Scotland's Census 2022 and Census 2021, Northern Ireland, 2021. Published 21 July 2026. https://openindex.co.uk/belfast/neighbourhood/n20000793#f-population - **Gigabit broadband coverage: 100.0%** (January 2026). In Castle B4, 100.0% of homes and businesses could get gigabit-capable broadband in January 2026 (Ofcom). UK 87.8%. Source: Connected Nations (Ofcom), January 2026. Published 13 May 2026. https://openindex.co.uk/belfast/neighbourhood/n20000793#f-gigabit-coverage - **Aged 15 to 64: 68.3%** (2021). 68.3% of residents in Castle B4 were aged 15 to 64 at the census (NISRA Census 2021). Joint 9,340th highest of 46,844. Source: Census 2021, England and Wales and Scotland's Census 2022 and Census 2021, Northern Ireland, 2021. Published 21 July 2026. https://openindex.co.uk/belfast/neighbourhood/n20000793#f-age-15-to-64 - **Aged 65 and over: 14.1%** (2021). 14.1% of residents in Castle B4 were aged 65 or over at the census (NISRA Census 2021). Joint 14,185th lowest of 46,844. Source: Census 2021, England and Wales and Scotland's Census 2022 and Census 2021, Northern Ireland, 2021. Published 21 July 2026. https://openindex.co.uk/belfast/neighbourhood/n20000793#f-age-65-and-over ## On the map - [Gigabit coverage by neighbourhood](https://openindex.co.uk/map/gigabit-broadband#place=N20000793) (Connected Nations (Ofcom) · January 2026): In Castle B4, 100.0% of homes and businesses could get gigabit-capable broadband in January 2026. - [Average house price by council](https://openindex.co.uk/map/house-prices#place=N20000793) (UK House Price Index · August 2026): Published for whole councils, so the map colours all of Belfast. The outline is Castle B4. - [Crime and ASB by neighbourhood](https://openindex.co.uk/map/recorded-crime#place=N20000793) (Police recorded crime and outcomes (data.police.uk) · August 2026): Police recorded 1 crime or anti-social behaviour incident in Castle B4 in August 2026. - [Population by neighbourhood](https://openindex.co.uk/map/population#place=N20000793) (Census 2021, England and Wales): Castle B4 had 525 usual residents at the census. Northern Ireland Multiple Deprivation Measure 2017 is published for the Super Output Areas (2001), whose boundaries differ from this neighbourhood’s, so it has no figure for Castle B4. [See deprivation across Belfast](https://openindex.co.uk/belfast/deprivation) ## How Castle B4 compares Each neighbourhood against every other neighbourhood the measure covers. | Measure | Castle B4 | Rank | Compared with | | --- | --- | --- | --- | | Population | 525 | 229th most populated | 735 neighbourhoods, Belfast · 2021 | | Gigabit broadband coverage | 100.0% | joint highest | 735 neighbourhoods, Belfast · Jan 2026 | | Aged 15 to 64 | 68.3% | joint 235th highest | 735 neighbourhoods, Belfast · 2021 | | Aged 65 and over | 14.1% | joint 340th lowest | 735 neighbourhoods, Belfast · 2021 | ## Is Castle B4 safe? What police records show In the 12 months to August 2026, police recorded crimes and anti-social behaviour in Castle B4 at a rate of 69.1 per 1,000 people. That compares with 51.3 per 1,000 people across Castle B. Across Northern Ireland as a whole, the recorded crime rate was 70.2 per 1,000 people. In August 2026 alone, 1 case of crime and anti-social behaviour was recorded in Castle B4. In the 12 months to August 2026, the most common types were violence and sexual offences (15), anti-social behaviour (7) and criminal damage and arson (7). Worked out by Open Index from police.uk crime records and ONS and NISRA population estimates. Rates are per resident, so places that many people work in or visit, such as Westminster, the City of London and other city centres, have far higher rates than their residents alone would suggest. ## Figures for the whole of Belfast These figures are published for the whole of Belfast, not for each neighbourhood, so they describe all of Belfast and not Castle B4 alone. [See Belfast](https://openindex.co.uk/belfast) - **Average house price: £184,768** (August 2026). Belfast’s average house price was £184,768 in August 2026 (HM Land Registry). Up 7.7% in a year. Source: UK House Price Index, August 2026. Published 21 October 2026. - **Population estimate: 351,927** (2025). Belfast’s population was an estimated 351,927 in mid-2025 (ONS population estimates). Down 0.1% in a year. Source: Mid-year population estimates, 2025. Published 1 October 2026. - **Female life expectancy: 80.5 years** (2022 to 2024). A baby girl born in Belfast could expect to live 80.5 years, based on deaths in 2022 to 2024 (ONS life expectancy). UK 83.0 years. Source: Life expectancy for local areas of the UK, 2022 to 2024. Published 10 December 2025. - **People in radon Affected Area squares: 14%** (2022). About 14% of people in Belfast live in a 1 km square that the radon atlas marks as a radon Affected Area. UK 44%. Source: Worked out by Open Index from the UKHSA and BGS radon atlas and census output areas. Published 1 December 2022. ## Castle B4 in brief Castle B4 had 525 usual residents at the census. In Castle B4, 100.0% of homes and businesses could get gigabit-capable broadband in January 2026. 68.3% of residents in Castle B4 were aged 15 to 64 at the census. 14.1% of residents in Castle B4 were aged 65 or over at the census. ## About - Type: Neighbourhood - Code: N20000793 - Middle area: [Castle B](https://openindex.co.uk/belfast/castle-b) - Ward: [Bellevue †](https://openindex.co.uk/belfast/ward/bellevue) - Constituency: [Belfast North †](https://openindex.co.uk/constituency/belfast-north) - Council: [Belfast](https://openindex.co.uk/belfast) - Nation: [Northern Ireland](https://openindex.co.uk/northern-ireland) - Area: 0.08 km² - People, mid-2024: 492 † Best fit: the ward and constituency this neighbourhood mostly lies in. Its edges do not follow theirs. ## Next door [Castle B3](https://openindex.co.uk/belfast/neighbourhood/n20000792), [Castle B2](https://openindex.co.uk/belfast/neighbourhood/n20000791), [Castle C3](https://openindex.co.uk/belfast/neighbourhood/n20000797), [Castle B1](https://openindex.co.uk/belfast/neighbourhood/n20000790), [Castle C1](https://openindex.co.uk/belfast/neighbourhood/n20000794) ## Latest updates for Castle B4 - August 2026 house prices published: HM Land Registry and partners · Oct 2026. - September 2026 rent published: ONS private rents · Oct 2026. - Nitrogen dioxide (NO2) updated: Defra · Oct 2026. - 2025 population published: ONS population estimates · Oct 2026. The same figures as JSON: https://openindex.co.uk/v1/places/N20000793 ## How to cite Source: Open Index, openindex.co.uk. Link to this page, https://openindex.co.uk/belfast/neighbourhood/n20000793, or to one figure with its anchor, https://openindex.co.uk/belfast/neighbourhood/n20000793#f-population. Open Index's own text and the figures it works out are licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Source data keeps its publishers' licences, named with each figure. Give each figure's period and source with it. Snapshot 2026.10.11. The HTML page: https://openindex.co.uk/belfast/neighbourhood/n20000793