British retail sales unexpectedly rose 0.5% in September, giving a lift to broader growth after a boost from tech sales, including Apple's new iPhone models, and demand for gold from online jewellers, official figures showed on Friday.

The Office for National Statistics said third-quarter sales growth of 0.9%, up from 0.2% in the second quarter, was likely to add 0.04 percentage points to third-quarter GDP growth, welcome news for an economy that has been forecast to slow in the second half.

Economists polled by Reuters had predicted that retail sales would fall 0.2% in September. Sterling rose against the dollar after the data.

Retail sales had performed relatively strongly over the summer, helped by unusually warm weather boosting clothing sales.

ONS statistician Hannah Finselbach said tech store sales had risen notably, while online jewellers reported strong demand for gold.

Gold prices on commodity markets have surged to record highs in recent weeks.

Retail volumes rise to highest since Q3 2022

September retail volumes were 1.5% higher on the year, where economists had expected a 0.4% rise, driven by the fastest growth in online spending since April 2021. For the whole quarter, overall volumes were up 1.0% to their highest in three years.

Britain's longest-running consumer survey, from GfK, rose slightly to give an October reading that was the joint-highest since August 2024.

However, many economists see clouds on the horizon.

"Against a backdrop of weak employment, high inflation and with tax rises on the horizon, we doubt the retail sector will be able to sustain this strength," said Alex Kerr, UK economist at Capital Economics.

Overall consumer spending has been subdued due to a high savings rate, which economists say may reflect 2022's surge in inflation, a more recent weakening in the jobs market and concerns about tax increases in November's budget.

Consumer inflation has held at 3.8% for three months - almost double the Bank of England's target - while wage growth is slowing and finance minister Rachel Reeves is expected to announce at least 20 billion pounds ($27 billion) of tax rises or spending cuts.

Updates from major retailers have been mixed.

Tesco, the biggest food retailer, raised its full-year profit forecast and said it was betting on a good Christmas. However, fast-food chain Greggs reported a further slowdown in sales growth and discounter B&M warned on profit twice in less than three weeks.

Online technology retailer Shopify said its survey showed British shoppers expected to spend an average of 181 pounds on seasonal goods such as advent calendars and Christmas ornaments, up from 159 pounds last year.