Everest said web development was fundamental to increasing its client database, and Equimedia was chosen to improve online performance by enhancing its pay-per-click contextual advertising technology.
Duncan Bland, marketing director at Everest, said: "We are committed to building online as a key element of our integrated recruitment strategy.
"In order to maximise our return on investment and drive down cost per acquisition it is important to work with an agency that has in-depth understanding of all online and direct channels."
Equimedia, which formed in January 2000, specialises in direct media campaigns, and lists First Plus, Halifax and Western Provident Association among its clients.
Everest has more than 2m UK customers, and sells home security, household furniture and conservatories.
Richard Davies, planning and client services director at Equimedia, said: "The win demonstrates that Equimedia is ahead of the market, firmly integrating digital and direct."
The win follows Equimedia's appointment to handle the direct marketing and online accounts for airport services firm Holiday Extras.
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