Costa Coffee took a hit from mild weather and fewer shoppers on the high street in the last three months, owner Whitbread (LON:WTB) said on Thursday.
Whitbread said the coffee shop chain boosted like-for-like sales by 0.5% in the 11 weeks to February 11, down from 6.9% in the equivalent period a year ago.
The company's budget hotel chain Premier Inn did slightly better, racking up a 2.2% rise in the period, although even that was well down on the 8.6% achieved last time.
Total group sales were up 1.7%, down from 5.8% a year earlier.
In the 50 weeks to February 11, like-for-like group sales were up 3.2% and Total sales lifted 10.4%, versus 6.5% and 13.3% beforehand respectively.
It attributed the sales fall at Costa to "an unusually warm winter" reducing demand for hot drinks, as well as fewer people visiting the shops.
At Premier, Total London revenue per available room and occupancy declined in a softer hotel market but Total sales were up 3.6% in the quarter. It increased the number of rooms available by 7.6%.
Restaurants, including Beefeater and Brewers Fayre among others, increased Total sales by 2.2% and like-for-like sales by 1% in the 50 weeks, which Whitbread said was ahead of rivals.
Chief executive Alison Brittain nevertheless said the company had traded well and expected to hit full-year profit targets.
"In the year ahead, as we build towards our growth milestones, we will continue to invest," she said.
Shares fell 149p, or 3.7%, to 3900p.
Broker Panmure Gordon said: "We continue to expect a slowdown in the pace of growth in 2016/17 which, combined with an increase in supply, is likely to push up cost inflation and weigh on returns.
"We believe pressure remains on the downside and retain our 'sell' recommendation."