Quick Answer: To measure acquisition efficiency at the account level, use metrics that tie spend to qualified revenue-bearing organizations, not individual leads. The most important are Account Acquisition Cost (total acquisition spend divided by new target accounts won), Account Conversion Rate by stage, Pipeline per Acquired Account, and CAC Payback at the account cohort level—because they show whether you are acquiring the right companies efficiently, not just generating low-cost contacts.
Account-level acquisition efficiency should be evaluated by how effectively marketing and sales convert spend into valuable, durable accounts with expansion potential. Instead of optimizing for contact volume, measure metrics that normalize for buying committees, multi-threaded engagement, and account quality: Account Acquisition Cost, Target Account Win Rate, Stage-to-Stage Conversion by account, Pipeline Velocity per account cohort, and Revenue per Acquired Account. These metrics reveal whether your acquisition engine is producing qualified organizations that progress through the funnel efficiently and generate meaningful pipeline and revenue, which is far more actionable than contact-level KPIs in complex B2B cycles.