SVS Savills Plc

LONDON—The U.K. housing market cooled in April for the first time in over a year, a fresh sign that uncertainty over the outcome of a coming referendum on Britain's membership of the European Union is weighing on the economy.

The Royal Institution of Chartered Surveyors said Thursday in a survey of more than 300 of its members that demand for homes in April fell, with the percentage of surveyors reporting a decline in new-buyer inquiries exceeding those reporting an increase by 22 points, the widest margin since March 2015.

The institution, which trains and accredits real estate surveyors world-wide, said the fall in demand was visible across the U.K. and in part reflects extra caution among home buyers ahead of the referendum June 23.

"Uncertainty is a word that features heavily in the feedback we are receiving from members," said RICS Chief Economist Simon Rubinsohn.

Higher property-transaction taxes introduced last month have also dented demand, Mr. Rubinsohn said. On April 1, a change to U.K. stamp duty added an additional 3% on buyers of second homes and rental properties.

Britain's market for high-end homes saw a spike in activity ahead of the new tax, according to U.K. real-estate broker Savills PLC. "Since then, the volume of activity has moderated, as we anticipated, in advance of the referendum," Savills said in a statement Wednesday.

The debate over the U.K.'s future in Europe stepped up a gear this week, with senior figures on both sides setting out their stall on what so-called "Brexit" might mean for the economy, Britain's influence in the world and its national security.

Polls show the public is split on whether to stay in the 28-member union or go it alone.

The economy has become a key battleground in the opposing campaigns, with supporters of Brexit arguing that Britain would be richer if it dumped onerous EU regulation and pursued new free-trade deals with fast-growing parts of the world.

Arrayed against them are institutions including the Organization for Economic Cooperation and Development, the International Monetary Fund and the U.K. Treasury, all of which warn leaving the EU would probably make Britain poorer than staying in the 28-member union.

Bank of England officials have said weakening business investment and slipping consumer confidence are among the signs that the economy is slowing ahead of the vote, as businesses and consumers put spending plans on hold until after the result is known.

Commercial property investors have paused ahead of the vote, with U.K. transaction volumes in the first quarter at £ 10.9 billion down 43% from the same period in 2015, according to data-provider Real Capital Analytics. Property chiefs have warned that a vote to leave the EU could cause commercial property values to fall, especially in London.

In the housing market, RICS expects prices to keep rising despite the dip in demand, given a shortage of new homes.

Write to Jason Douglas at jason.douglas@wsj.com and Art Patnaude at art.patnaude@wsj.com

(END) Dow Jones Newswires

May 11, 2016 19:25 ET (23:25 GMT)

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