Costa Coffee, the UK’s largest coffee shop chain, this morning revealed it had seen a 20.5% rise in underlying profit to £43.5m, up from £36.1m.Costa parent company Whitbread, which also runs pubs, restaurants and hotels, revealed its interim results for the six months to 29 August 2013, noting that sales at Costa had also increased by 20.9%, worldwide system sales were up by 19.5% and like-for-like (LFL) saleswere up 5.5%.Overall for Whitbread, total revenue was up by 12.4% to £1.14bn, up from £1.01bn and group sales increased by 2.8%.Andy Harrison, Whitbread’s chief executive, said: “Costa, the UK’s favourite coffee shop, continued its excellent performance, opening 153 net new stores worldwide and growing total system sales by 19.5%. UK system sales grew by 19.6%, with strong consumer demand driving a 5.5% growth in UK LFL sales. We celebrated the opening in Bangkok of our 1,000th Costa international store. “This good first-half performance puts us on track to deliver this year’s business plan and we remain on the right trajectory for our 2016 and 2018 growth milestones. Our combination of strong organic growth, good returns on capital and strong cash flow should continue to create substantial shareholder value.”During the first half, Costa opened 86 net new stores in the UK taking the total number of stores to 1,664, over 800 more than its closest competitor.