UK data centre take-up continues to concentrate on London as lack of power capacity intensifies
19mw of UK existing data centre capacity was taken-up in Q1, says Savills, as a lack of available options following a record year of take-up in 2025 begins to take effect.
According to Savills, the UK’s data centre vacancy rate has compressed sharply in the last decade, from 27% in 2016 to 8% in Q1 2026, with London’s vacancy rate currently even lower at just 7%. A record amount of capacity – 217mw – took space across the country in 2025, up from 212mw in 2024, with 96mw taken in the final quarter of 2025 alone.
The international real estate advisor says that UK data centre demand is converging on a limited pool of capacity that can be delivered in the right places and within occupiers’ timeframes. While options to expand beyond the capital are increasingly considered, existing and future supply and occupier focus remains still largely concentrated in London where cloud ecosystems, network density and established availability zones continue to anchor site selection, says Savills. However, this competition for sites in and around the capital is intensifying pressure on power, land and delivery timelines. According to Savills, London currently accounts for 1,637mw (91%) of the UK’s total live capacity of 1,803mw, up from 81% in 2016.
While Savills says that UK-wide expansion will increase national capacity in the long-term, outside the London orbit the cloud market currently remains comparatively shallow as developers favour building on existing infrastructure networks, where connectivity is already established and development risks are lower.
In 2025, 231mw of IT capacity was delivered in the UK after 191mw was delivered in 2024, two record annual highs. That step-change has not yet been repeated in 2026, with 48mw delivered in Q1. Of the 242mw currently under construction across the UK, around 66mw is scheduled to complete between Q2 and Q4 2026, underscoring how limited the immediate delivery window is relative to the headline pipeline.
Rupert Duckworth, associate director, Savills Data Centre Advisory, comments: “National supply is expanding on paper, but much of the pipeline remains early-stage and uncertain. Pre-letting has become a core feature of the market, with future capacity increasingly committed well before completion.
“While activity remains anchored to tier-one locations around London, with Manchester cited secondary, beyond these two cities activity is limited reflecting how difficult it remains to deliver network density, occupier ecosystems and timely access to power. Having said that, we are forecasting growth in the North East given its renewable infrastructure and grid connectivity, and by a planning context that is more receptive to large-scale investment. Even so, this is best understood as a medium-term diversification story rather than an immediate release valve for the broader market.”
Lydia Brissy, director, European Research, Savills, adds: “Looking ahead, the UK’s unlikely to lack data centre demand, capital or strategic relevance. The decisive question is which projects can deliver capacity in a more constrained, regulated and execution-sensitive environment. The direction of travel is clear: delivery certainty is increasingly shaped by energy strategy as much as by real estate fundamentals. London’s growing share of national capacity heightens exposure to grid scarcity and long connection lead times. Market conversations suggest that, in some of the most constrained West London locations, developers are now planning for multi-year waits for firm capacity, long enough for operators to start to consider alternative power solutions less as a contingency plan than a strategy; using them to bridge the gap to grid capacity and secure position in the right locations.”