Costa Coffee has announced a blanket ban on smoking in all its UK outlets.
The coffee-shop chain already has 90% of its 370 UK outlets shops no-smoking.
Research by the company showed that 63% of Costa customers were non-smokers and 80% preferred a smoke-free environment.
Mark Phillips, managing director, said: "Typically we see an increase in food sales when we convert a store to non-smoking. We expect a similarly positive reaction from our customers when we transform the remaining 10%."
Deborah Arnott, director of anti-smoking campaign group ASH, applauded the decision.
"Second-hand smoke is a serious health hazard for staff in the hospitality trade and research shows that more than half of all adults want to eat and drink in smoke-free places," she said.
Costa owner Whitbread has already introduced a smoking ban at its 600-plus Pizza Hut restaurants in the UK.
By Amy Abrahams
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