Retainer Coverage Ratio

Retainer Coverage Ratio measures how much of a monthly client retainer the email platform fee consumes before any agency labor is billed. On a 5,000-contact list, most platforms in this category cost $30 to $80 per month, so a $500 retainer leaves roughly 85% for strategy, copy, segmentation, and sends. The ratio collapses when agencies quote platform access as the deliverable: the tool fee is too small to defend a retainer on its own, and the client eventually notices they could buy the same seat directly. Agencies that win bundle list growth, segmentation, creative, and sends into one scope, then price the platform as a pass-through line item rather than the product. A client that has outgrown its tool mid-campaign faces a disruptive migration, which is why platform fit gets audited against list size and funnel stage before renewal, not after.