The Scottish firm said costs of the aborted deal add up to £4.9m, helping knock profits during the six months to the end of July by 10% to £13.2m.
Barr, which dates back to 1875 and also makes Tizer and Rubicon, called time on the £1.4 billion merger in July after Hertfordshire-based Britvic rejected a sweetened revised approach.
But the group, based in Cumbernauld near Glasgow, said it "successfully navigated" a tough market despite the distraction of the deal.
July's heatwave helped it compensate for intense competition, with rivals fighting for market share by slashing prices after the freezing start to the year. Barr said the "depth and quantum" of promotions has continued to accelerate.
It said Irn-Bru - dubbed Scotland's other national drink - was bolstered by a TV advertising campaign, while Rubicon and Barr brands achieved good growth thanks to better availability.
Barr said the brands maintained "strong market positions" as it grew sales by 5.8% to £128.7m.
The total soft drinks market rose 4.5%.
Charles Pick, analyst at Numis Securities, said: "Barr has again outpaced the overall soft drinks market... and the outlook statement is a confident one."