MQL vs SQL: Fix the Handoff With a Shared Definition and a Leakage Metric

What Is the Difference Between an MQL and an SQL?

A marketing qualified lead is a contact marketing believes is ready for a sales conversation. A sales qualified lead is a contact sales has agreed to work. The two terms look like adjacent rungs on one ladder, but the space between them is where most B2B pipeline quietly disappears. An MQL is a prediction. An SQL is an acceptance of that prediction. When the two teams score against different definitions, every lead that crosses the line turns into an argument instead of an opportunity.

We build forecast models for revenue teams, and the marketing-to-sales handoff is the first place I look when a pipeline number refuses to reconcile. The cause is rarely lead volume. It is that nobody wrote down what qualified means, so marketing counts one thing and sales counts another, and the leads caught in between fall through a seam no report is watching.

Why Does the MQL to SQL Handoff Leak?

The handoff leaks because MQL and SQL are owned by two teams with opposite incentives and no shared contract. Marketing is measured on volume of qualified leads, so its threshold drifts down until a whitepaper download counts as intent. Sales is measured on closed revenue, so it discards anything that looks thin without recording why. Both teams behave rationally, and the pipeline absorbs the cost.

The damage is not the disagreement. It is that the disagreement is invisible. A rejected MQL that gets no reason code teaches marketing nothing, so the next batch looks identical. A passed MQL that a rep never touches does not show up as churn or as a loss. It shows up as nothing. This is a pipeline-integrity problem before it is a lead-quality problem, because you cannot trust a funnel whose largest leak is unmeasured.

What Does a Shared MQL-to-SQL Definition Look Like?

A shared definition names the exact criteria a lead must meet to change hands, and the exact action that records the change. It lives in one document both teams sign, and it treats the handoff as a transaction with a receipt, not a hope. The two lines that matter most are the exit rule and the reject rule, because they force a disposition. A lead cannot sit in limbo. It is accepted with a logged next step, or it is returned with a reason. Lead scoring sets the marketing threshold, but the sales acceptance step is what converts a marketing qualified lead into a real sales qualified lead. Skip the acceptance step and you have a routing rule wearing a qualification badge.

Which Metric Exposes a Broken Handoff?

One number tells you whether the handoff holds: the share of MQLs that reach sales and receive no disposition at all. Sales neither accepted them nor rejected them, and no one logged a single action against them. That silent bucket is your handoff leakage, and it is more honest than any conversion rate, because conversion rates only count the leads someone bothered to process.

Here is an illustrative month, not a benchmark. Say marketing passes 1,000 MQLs:

The 16% is the number to govern against. Those 160 leads are invisible to both teams. Marketing books them as delivered and sales never records an opinion, so forecasting cannot price them because they carry no signal. A sales accepted lead step exists precisely to shrink that middle bucket toward zero. Every lead gets a yes with a next step or a no with a reason, and the leakage rate becomes a weekly gauge instead of a quarterly surprise.

How Do You Know an SQL Is Real and Not Stalling?

An SQL is real while it keeps producing meaningful activity, and it is stalling the moment that activity goes quiet. At ORM we define meaningful activity as a change in stage, close date, or amount. Notes and calls matter, but those three fields are the ones that move a deal on the board. When they stop moving, the deal has stopped too, whatever the rep says on the forecast call.

The strongest early warning is the absence of a signal, not a bad one. In our data the earliest risk marker on any opportunity is silence, meaning no logged activity and no change to the fields that matter. A freshly accepted SQL that produces nothing in its first two weeks is already leaking, and it will read as healthy on a coverage report right up until the close date slips. Across the pipelines we model, more than 10% sits stale, untouched for twelve months, still counted in coverage and worth nothing. An SQL definition that requires logged activity is what stops today's clean handoff from becoming next quarter's stale line.

How Do You Fix the Handoff for Good?

Put both teams on one written definition, then govern the silent bucket as a weekly leakage number instead of a quarterly conversion report. None of that requires perfect data. Everyone believes their CRM is uniquely messy, and it does not matter. As long as the way you record a disposition is consistent, the leakage number is trustworthy and the trend is real. Garbage in does not have to mean garbage out when the garbage is consistent.

The payoff is a funnel you can forecast forward instead of only audit backward. When the pipeline coverage you report is built on SQLs that were each accepted against one definition and are each still generating activity, the coverage number finally means what executives assume it means. Fix the MQL-to-SQL handoff and you are not chasing better leads. You are closing the seam that was draining the ones you already had.