# Black Mountain J6 South west Belfast. 253 people (mid-2024 estimate) in 1.0 square kilometre. Black Mountain J6 had 251 usual residents at the census (NISRA Census 2021). Neighbourhood. Code N20001336. In: [Northern Ireland](https://openindex.co.uk/northern-ireland) › [Belfast](https://openindex.co.uk/belfast) ## Key figures - **Population: 251** (2021). Black Mountain J6 had 251 usual residents at the census (NISRA Census 2021). Joint 89th 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/n20001336#f-population - **Gigabit broadband coverage: 83.9%** (January 2026). In Black Mountain J6, 83.9% 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/n20001336#f-gigabit-coverage - **Aged 15 to 64: 51.4%** (2021). 51.4% of residents in Black Mountain J6 were aged 15 to 64 at the census (NISRA Census 2021). Joint 1,218th 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/n20001336#f-age-15-to-64 - **Aged 65 and over: 33.1%** (2021). 33.1% of residents in Black Mountain J6 were aged 65 or over at the census (NISRA Census 2021). Joint 2,722nd 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/n20001336#f-age-65-and-over ## On the map - [Gigabit coverage by neighbourhood](https://openindex.co.uk/map/gigabit-broadband?place=N20001336) (Connected Nations (Ofcom) · January 2026): In Black Mountain J6, 83.9% 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=N20001336) (UK House Price Index · August 2026): Published for whole councils, so the map colours all of Belfast. The outline is Black Mountain J6. - [Crime and ASB by neighbourhood](https://openindex.co.uk/map/recorded-crime?place=N20001336) (Police recorded crime and outcomes (data.police.uk) · August 2026): Crime and anti-social behaviour for Black Mountain J6. - [Population by neighbourhood](https://openindex.co.uk/map/population?place=N20001336) (Census 2021, England and Wales): Black Mountain J6 had 251 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 Black Mountain J6. [See deprivation across Belfast](https://openindex.co.uk/belfast/deprivation) ## How Black Mountain J6 compares Each neighbourhood against every other neighbourhood the measure covers. | Measure | Black Mountain J6 | Rank | Compared with | | --- | --- | --- | --- | | Population | 251 | 26th least populated | 735 neighbourhoods, Belfast · 2021 | | Gigabit broadband coverage | 83.9% | joint 42nd lowest | 735 neighbourhoods, Belfast · Jan 2026 | | Aged 15 to 64 | 51.4% | 12th lowest | 735 neighbourhoods, Belfast · 2021 | | Aged 65 and over | 33.1% | 13th highest | 735 neighbourhoods, Belfast · 2021 | ## Is Black Mountain J6 safe? What police records show In the 12 months to August 2026, police recorded crimes and anti-social behaviour in Black Mountain J6 at a rate of 1,379.4 per 1,000 people. That compares with 259.6 per 1,000 people across Black Mountain J. Across Northern Ireland as a whole, the recorded crime rate was 70.2 per 1,000 people. In August 2026 alone, 45 cases of crime and anti-social behaviour were recorded in Black Mountain J6. In the 12 months to August 2026, the most common types were shoplifting (173), violence and sexual offences (56) and anti-social behaviour (54). 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 Black Mountain J6 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. ## Black Mountain J6 in brief Black Mountain J6 had 251 usual residents at the census. In Black Mountain J6, 83.9% of homes and businesses could get gigabit-capable broadband in January 2026. 51.4% of residents in Black Mountain J6 were aged 15 to 64 at the census. 33.1% of residents in Black Mountain J6 were aged 65 or over at the census. ## About - Type: Neighbourhood - Code: N20001336 - Middle area: [Black Mountain J](https://openindex.co.uk/belfast/black-mountain-j) - Ward: [Falls Park †](https://openindex.co.uk/belfast/ward/falls-park) - Constituency: [Belfast West †](https://openindex.co.uk/constituency/belfast-west) - Council: [Belfast](https://openindex.co.uk/belfast) - Nation: [Northern Ireland](https://openindex.co.uk/northern-ireland) - Area: 0.96 km² - People, mid-2024: 253 † Best fit: the ward and constituency this neighbourhood mostly lies in. Its edges do not follow theirs. ## Next door [Botanic U2](https://openindex.co.uk/belfast/neighbourhood/n20001149), [Black Mountain F2](https://openindex.co.uk/belfast/neighbourhood/n20001320), [Black Mountain R1](https://openindex.co.uk/belfast/neighbourhood/n20001350), [Black Mountain J3](https://openindex.co.uk/belfast/neighbourhood/n20001321), [Black Mountain H4](https://openindex.co.uk/belfast/neighbourhood/n20001340), [Black Mountain J4](https://openindex.co.uk/belfast/neighbourhood/n20001322) ## Latest updates for Black Mountain J6 - 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/N20001336 ## How to cite Source: Open Index, openindex.co.uk. Link to this page, https://openindex.co.uk/belfast/neighbourhood/n20001336, or to one figure with its anchor, https://openindex.co.uk/belfast/neighbourhood/n20001336#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 2026.10.9. The HTML page: https://openindex.co.uk/belfast/neighbourhood/n20001336