Price comparison website Moneysupermarket.com said it has lost out recently in the battle for car insurance customers after changes by search engine Google.
The group said visitor numbers and revenues in the highly-competitive car insurance market slowed in June after Google changed "natural search algorithms" - pushing its website down the rankings in searches.
But Moneysupermarket said it is working to climb the search rankings again, adding results for the six months to the end of June will be in line with its expectations. Underlying earnings are up 29% to £40 million and revenues are 10% higher at £112 million.
Google last year launched its own price comparison service, which appears high up during internet searches.
But Moneysupermarket said the slowdown in second-quarter trading was not due to tougher competition from Google's new service, adding that the search engine giant regularly changes its algorithms.
It said: "As has happened in the past, now the algorithm changes have settled down we are working on regaining our positions in natural search in insurance."
The company added its finances remain strong, with cash of £26 million. It will pay a special dividend of £70 million on July 26.
Shares were down about 2% but analyst Simon Davies at Canaccord Genuity said the results were modestly ahead of its expectations.
He said: "Moneysupermarket has faced considerable headwinds in its first half, but has still managed to deliver 10% revenue growth."