The firm said the deal would expand its array of performance-based online marketing platforms and boost its presence in Europe. Pricerunner is the third-most popular comparison site in the UK, behind Kelkoo and DealTime, and also operates in France, Germany and Sweden.
The £15.8m agreement includes cash and about 263,000 shares of ValueClick common stock shares issued to three management shareholders of Pricerunner. An extra consideration worth $6m is dependent on Pricerunner's performance.
ValueClick is aiming to take advantage of the anticipated growth in European online retail sales, which Forrester Research forecasts will grow from EUR40bn (£26.8bn) in 2004 to EUR167bn (£112bn) in 2009.
James Zarley, CEO of Value-Click said: "We've been looking to add comparison shopping as part of our strategic growth plan."