MQL (Marketing Qualified Lead) to SQL (Sales Qualified Lead) conversion rate is the percentage of MQLs that are converted to an SQL. An MQL is a lead that marketing believes meets the criteria of a qualified prospect, and an SQL is a lead that sales has independently qualified and believes meets the criteria of a qualified prospect.

A Marketing Qualified Lead (MQL) represents a prospect who has demonstrated sufficient engagement and intent to warrant sales attention, based on criteria established collaboratively between marketing and sales teams. Unlike raw leads or contacts, MQLs have crossed specific behavioural or demographic thresholds that indicate genuine interest in your solution. This metric serves as marketing's primary deliverable to sales and forms the backbone of most demand generation strategies, with teams typically setting targets for both MQL volume and quality measures such as MQL-to-SQL conversion rates.