MQL vs SQL vs Lead vs Prospect: The Funnel Stages Explained

Includes: Funnel-stage definition table: lead → prospect → MQL → SQL reference
The short answer

A lead is a maybe, a prospect is a fit you've engaged, an MQL is marketing-qualified, and an SQL is a sales-qualified lead worth a meeting. This page gives you the funnel-stage table that maps who qualifies what — and why the SDR's core job is converting MQLs into SQLs and booked meetings.

The funnel has four words people use interchangeably, and the confusion costs you: a lead is a maybe, a prospect is a fit you've actually engaged, an MQL is a lead marketing has scored, and an SQL is a sales-qualified lead worth a meeting. The SDR turns inbound MQLs into SQLs and qualified meetings; the BDR turns the prospects it creates into SQLs too. Same end point, different front half. This page gives you the table.

The funnel-stage table

Here is the asset:

Stage What it is Who qualifies it Example
Lead A person/company with a faint sign of interest Nobody yet Downloaded a whitepaper
Prospect A lead that fits your ICP and you've engaged You (research + outreach) Fits the ICP, replied to one message
MQL A lead marketing scored as a likely fit Marketing (score/form/downloads) Passed a fit score, not contacted
SQL A lead sales has qualified — real problem, budget, authority, timeline Sales (you) Head of ops, migrating this quarter, budget approved
Qualified meeting The SQL, booked on the AE's calendar You, after a discovery call Confirmed + showing up

What turns a lead into an SQL

Two things separate an early lead from an SQL: fit and qualification. Fit is the ICP — is this the type of company where you win. Qualification is asking the questions that confirm problem, budget, authority, and timeline. Marketing can score fit; only sales can qualify. That is the SDR's core value: it takes an inbound maybe and makes it a qualified yes, so an account executive's calendar only fills with meetings worth having.

Why the labels matter

The labels exist so the pipeline is honest. Call everything a lead and you can't tell a maybe from a qualified yes; the AE books a meeting and it's a dead end. Keep the stages sharp and you protect your reputation and your quota attainment: qualified meetings that show up are the number that matters, and you can only hit it by being ruthless about what you call an SQL.

Start here

You can tell a maybe from a qualified yes. The last piece of the module is the machine that turns them into booked meetings — how many touches a sequence needs, and how to build a 14-day cadence that converts.

Practice this

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