Revenue rose 14.5 per cent to £805m as the company expanded its operations across the UK.
Whitbread raised its interim dividend by 17 per cent to 11.25p to reflect the results.
Costa has just over 1,100 in the UK – and plans to take the total to 1,850 by the end of the year.
Like-for-like sales at coffee stores chain Costa rose 8.5 per cent, boosted by new products such as the flat white and ice cold Costa, and a customer loyalty card.
Whitbread also plans to expand its Premier Inn hotel chain, and open at least 1,700 rooms in 18 hotels across the UK.
It says its advertising campaign, fronted by the comedian Lenny Henry, promoting its £29 a room offer helped to boost like-for-like sales by 10.1 per cent.
In London, a rise in the number of tourists over the summer also helped the Premier Inn business.
Chief executive Alan Parker, who was reporting his final set of results, said: “People want value for money and Whitbread is benefiting from these times of austerity.
“In London the number of tourists over the summer helped us. This is a great business based on a solid grounding.
“Our Premier Inn offers for periods of low occupancy are really paying off.” Andy Harrison has arrived from easyJet to take over as chief executive.
Premier Inn was voted UK’s favourite hotel brand according to a YouGov survey.
The group also owns the Beefeater and Brewers Fayre pub restaurant chains. Parker added: “In our markets we feel in a fairly buoyant position.”