Price Index Methodology
What the index measures
The Spacebly UK Flexible Office Price Index reports the quoted cost of one desk, per month, in flexible and serviced office space. All figures are in GBP and exclude VAT. It is a measure of asking prices, not transacted deals.
Data source
Every figure is derived from live listings published on Spacebly by the operators and landlords who own the buildings — approved, publicly visible UK buildings carrying at least one suite-level monthly desk rate quoted in GBP.
City assignment
A building is assigned to a city hub by exact city-name match, then by geographic proximity to the nearest hub centre within that hub's radius (32km for London, 15–20km elsewhere). Buildings outside every hub radius are excluded.
Calculation
- Each qualifying suite contributes one observation: its lowest quoted monthly rate per desk.
- Observations below £50 or above £5,000 per desk per month are discarded as data-entry errors.
- Percentiles (25th, median, 75th) are computed with linear interpolation.
- A city is published only with at least 10 qualifying observations in the month.
- The national figure spans all qualifying observations across published hubs.
Update frequency
Each monthly release is a point-in-time snapshot of live listing data and is frozen when first published. The inaugural August 2026 release was captured on 18 August 2026; later releases are captured when that month's snapshot is first published.
Limitations
- Asking rates are not achieved rates.
- The index is weighted by suite, not by desk count or floor area.
- Smaller markets have thinner samples and noisier medians.
- Inclusions bundled into quoted rates are not normalised between operators.
Confidence and monthly updates
Each city figure carries a confidence label. Robust means at least 30 buildings and 100 quoted desk rates. Indicative means 10 to 29 buildings and at least 30 rates; treat it as a guide. Below that we publish only the count and the lowest and highest rates, with no median.
From November 2026 each snapshot also includes a "UK excluding London" figure, so regional rates are not pulled up by London.
A new snapshot is captured on the 1st of each month and frozen. Each month and city has its own permanent address, for example /price-index/2026-10/london, so citations keep pointing at the figure that was quoted. The CSV lists quoted_rates (the old desks column stays for three releases), confidence and published.