Belfast population: 345,006 residents, but check the date and boundary
Belfast’s population is recorded as 345,006 on 1 July 2021. The figure is dated and uses a specific boundary, so it shouldn’t be treated as a current metropolitan total.
Belfast’s population is recorded as 345,006 residents on 1 July 2021 in its population record. This is a dated figure, not a current population count, and should not automatically be treated as the population of the wider metropolitan area.
Population in Belfast: the dated figures
| Measure | Figure | Reference date |
|---|---|---|
| Population | 345,006 | 1 July 2021 |
| Population density | 3,000 people per km² | 1 July 2021 |
| Area | 115 km² | 9 October 2026 |
These entries appear in the Belfast record. The area has a different reference date from the population and density, so the three entries should not be presented as a single, newly measured snapshot.
Population of Belfast over time
The historical population entries list 333,871 residents in 2015 and 345,006 on 1 July 2021. The earlier entry specifies a year rather than a complete calendar date. These two observations alone do not establish a continuous annual growth trend.
Why the boundary matters
A place name can act like a mask: two figures labelled “Belfast” may look comparable while concealing different geographic footprints. Before comparing totals, check whether each counts the city, a local government district or a metropolitan area, then match the reference dates.
The figures above do not establish a separate metropolitan total or a demographic breakdown. They should not be relabelled as either.
