AI firms accounted for almost one-fifth (19 per cent) of all Central London office take-up in the second quarter of the year, according to the latest Central London Office Analysis from Avison Young. Central London office take-up totalled 2.6m sq ft in Q2 2026, over a third higher (36.8 per cent) than in Q1, representing the strongest quarter for take-up in a year. Deals over 50,000 sq ft rose 50 per cent above the post-covid average. The AI sector took approximately 500,000 sq ft of space, bringing H1 take-up to 700,000 sq ft. Activity was concentrated in the King’s Cross/Euston area, boosted by the completion of Google’s 860,000 sq ft headquarters. Prime rents increased, with quarterly prime rental growth reaching 6.5 per cent between Q2 2025 and Q2 2026, with the strongest growth in Mayfair, St James’s and Canary Wharf. Office vacancy levels remained stable at 6.3 per cent, with Midtown falling to 4.3 per cent. Grade A vacancy reached 1.9 per cent, standing as low as 1.3 per cent in the West End and the City. James Walker, Principal and Head of London Office Leasing at Avison Young, said AI continues to be at the center of demand, and while Grade A vacancy remains