The average agency review costs a combined $1 million for marketers and agencies involved, according to a study by Advertiser Perceptions commissioned by the Association of National Advertisers and 4A’s.
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That average is based on reviews with three agencies and no incumbent involved. Reviews with more agencies or with an incumbent likely cost more, according to the study. An incumbent agency spends on average $406,092 defending an account—which is likely why 25% of incumbents decline to participate in reviews.