The account will include television activity as well as direct campaigns for the insurance provider. Rhythmm, a full-service agency, will retain the creative work.
Andrew Mason, head of direct at MindShare Direct, said: "We are determined to deliver the business goals together."
Endsleigh is an independent specialist in car, home and travel insurance, life cover and mortgages.
Stuart Wartalski, head of corporate communications at Endsleigh, said: "It is important to work with a team that cares about our business goals as much as we do. MindShare Direct has shown a level of enthusiasm and hunger for success that is very reassuring."
MindShare Direct will add the account to recent wins including catalogue retailer Boden and family photographic studios Olan Mills.
Endsleigh competes against larger insurance providers including Aviva, incorporating the Norwich Union and RAC motoring insurance brands, the Royal Bank of Scotland-owned insurer Churchill and Direct Line, who have diversified from motor insurance to challenge other providers in the home and travel categories.