UK economy expands 0.7% in third quarter as AI provides 'extra engine of growth'

Britain's economy expanded 0.7% in the July-to-September period, matching consensus forecasts but accelerating from a revised 0.5% in the second quarter and marking the strongest calendar-quarter growth since Q1 2024. Annual GDP rose 1.9%, the highest since late 2024, while September alone delivered a 0.2% monthly gain after a flat August, the fifth consecutive month of above-consensus readings. The services sector powered the advance with a 0.9% increase, led by information and communication which jumped 2.1%. Within that, computer programming, consultancy and related activities surged 4.4% and emerged as the single largest contributor to GDP growth across 2026, with the Office for National Statistics noting that many of the firms reporting the biggest turnover gains operate in artificial intelligence and cloud computing. Manufacturing also leaned into the trend: output of computer, electronic and optical products climbed 4.6% in the three months to September, the biggest driver of industrial production. Meanwhile production as a whole edged up just 0.1% and construction contracted 0.7%, underscoring how narrowly based the expansion remains.

The Bank of England last week raised its key rate to 4% for the first increase since August 2023 and upgraded its 2026 growth forecast to 1.6% from 1.1% in July, explicitly citing AI-related business investment as a factor. Inflation stood at 3.5% in September, driven by household energy bills and motor fuel prices, and the Monetary Policy Report warned it could approach 5% by mid-2027 unless the US-Iran war eases. Chancellor John Healey called the figures evidence of "stand-out resilience" and said growth was the fastest in nearly a decade outside the pandemic rebound, while Prime Minister Andy Burnham described them as "bringing hope for the future." Yet the ONS cautioned that its data collection cannot yet quantify the exact impact of AI activities on turnover, and economists including Suren Thiru of ICAEW and Scott Gardner of J.P. Morgan warn that higher employment costs, persistent energy prices and budget uncertainty will test the economy's momentum in the final quarter and into 2027.

The Bank's November report itself envisages weaker growth in the last three months of 2026 and into next year, even as it acknowledges activity has been more resilient than expected. Britain's Q3 pace was the second-fastest in the G7 behind only the United States, and year-to-date growth is the strongest since 2017 excluding the post-pandemic bounce. But the expansion rests heavily on a cluster of AI-linked services and hardware manufacturing that statistical agencies still struggle to measure precisely, while the broader economy contends with natural gas prices roughly three times their pre-war level and wholesale electricity costs double year-ago levels.

The central question for policymakers and investors is whether the AI investment cycle has enough breadth and durability to sustain growth once the energy shock and higher borrowing costs fully transmit. December's rate decision will hinge on incoming monthly GDP, inflation and labour-market data, with the BoE signalling further hikes are possible unless the Middle East conflict resolves. For now, the UK has defied the post-war slowdown predictions, but the foundations remain unusually concentrated and the statistical picture incomplete.