MQL, SQL, SAL: These abbreviations sound like corporate marketing, and many small B2B teams dismiss them. And rightly so, in part. But behind these terms lies a question that every company generating leads must answer: When is an inquiry actually valuable?
The terms explained in simple terms
An MQL (Marketing Qualified Lead) is a request that looks promising from a marketing perspective: suitable company size, suitable role, and genuine interest is evident. An SQL (Sales Qualified Lead) is a request that sales has reviewed and accepted: this is a lead worth pursuing. In between lies the handshake, sometimes called SAL (Sales Accepted Lead): the moment when sales officially takes over the lead instead of letting it sit.
Why the definition is more important than the term
A lead is only valuable if marketing and sales have the same understanding of what it means.
The most common pattern I see: Marketing celebrates 50 leads, sales says "none of them were worthwhile," and both are right because no one has defined what "worthwhile" means. Without a shared definition, the campaign optimizes for a number that's useless to sales, and sales ignores inquiries that have cost money.
What small teams really need
You don't need a five-stage funnel nomenclature. You need exactly one question answered collectively: What criteria must a request meet for sales to seriously consider it? Company size, budget signal, sender's role, specific need—three to four criteria are sufficient. Document this definition, keep it in your CRM or a simple spreadsheet, and measure campaigns against this exact metric, not the raw lead count. That's the whole magic behind the acronyms.
Frequently Asked Questions
Do we, as a company with 10 people, really need MQL/SQL definitions?
The terms themselves aren't important, but the definitions are. Even with two inquiries per week, it must be clear which ones sales is seriously pursuing and why. Otherwise, you can't evaluate your marketing expenditures.
Who sets the criteria, marketing or sales?
Both together, otherwise it won't work. Sales knows which inquiries will lead to sales, and marketing knows which signals can be specifically targeted in campaigns.
How many criteria should a lead definition have?
As few as possible. Three to four hard criteria that can be checked on the form or during initial contact are far better than a twenty-point list of criteria that nobody uses.
What happens to requests that do not meet the criteria?
Don't throw them away, but keep them separate. Some of them will become relevant later, for example, as the company grows. But they don't belong in the same performance measurement as qualified leads.
How to incorporate this definition into campaign measurement is explained in Cost per Lead in B2B and B2B Conversion Tracking. Or we can define your criteria together in the Analysis discussion.