The agency employs 38 people directly on Unilever, which it has lost as part of a Western European consolidation into MindShare.
However, Jerry Hill, the agency's chief executive, said the account does not move to MindShare until next July, and he hopes to be able to pull in new business to cover part of the Unilever loss.
The £196m (according to Nielsen Media Research) account represents Unilever's entire UK spend and amounts to 40% of Initiative's UK billings. However, its "real" spend is lower because of the discount it receives from media owners.
Hill said: "We have the business until the middle of next year and my view is not to overreact. No agency is dependent on just one client.
"The account is managed separately from the rest of our business so it will not distract us from our other clients."
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