Leads in marketing: what the word means, the five stages, and the definitions to write down

In marketing, a lead is a person or organisation that you can identify, that you have a way of contacting, and that has shown some signal of interest in what you sell. All three parts have to be present. A name with no contact route is a mention. An email address collected with no interest shown is a list entry. Interest shown by somebody you cannot contact is traffic. Everything else the industry argues about, enquiry, prospect, MQL, SQL, opportunity, describes how far along that lead has travelled, and the arguments between sales and marketing almost always come from those words never being written down.

The definition, in three parts

• Identified. You know who they are, at the level your business sells at. For a business to business sale that means a person and a company. For a consumer sale, a person.
• Contactable. You hold a phone number, email address or messaging handle, and you hold it with permission to use it.
• Interested. They did something that signals interest: filled in a form, asked for a quote, booked a demo, started a trial, replied to an outbound message, walked into the showroom.

A clean definition settles most disputes on its own. A downloaded report from somebody in a country you do not serve meets two of the three parts and fails the third in practice, which is why the definition should carry your own qualifying criteria alongside it.

The five stages, and the definition to write down for each

Stage	Definition to agree	Owned by	What moves it forward
Contact or subscriber	Identified and contactable, no interest signal yet	Marketing	Any action that signals interest
Lead	Identified, contactable, one interest signal recorded	Marketing	Meeting the agreed fit and intent criteria
Marketing qualified lead	Matches the target profile and has shown buying intent, scored against written criteria	Marketing, with sales agreement on the criteria	Acceptance by sales within the agreed time
Sales qualified lead	Accepted by sales after a conversation that confirmed need, authority and timing	Sales	An agreed next step with a date
Opportunity	A named deal with a value and an expected close date	Sales	The sales process

Write these five definitions on one page, get both teams to sign it, and put the date on it. That single page removes the recurring argument about whether the leads were any good, because the criteria are now a document rather than an opinion.

The words that get used interchangeably and should not be

Word	What it actually means
Enquiry	An inbound request, usually for a price or availability. Every enquiry is a lead. Not every lead is an enquiry
Prospect	A lead that has been qualified as a plausible buyer. The step after lead, before a deal exists
Contact	A record in your database. A contact becomes a lead when an interest signal is attached
Suspect	A company that fits your profile and has shown nothing. A target, not a lead
Opportunity	A deal with a value and a date. Counted in pipeline, not in lead volume
Conversion	Any defined step being completed. Always state which step you mean

Lead qualification, kept simple

Qualification has two halves, and keeping them separate is what makes a scoring model useful.

• Fit. Are they the kind of customer you serve? Industry, size, location, and whether they can afford you. Fit is known from firm data and barely changes.
• Intent. Are they in the market now? Pricing page visits, a demo request, a quote request, repeat visits in a short window, replies to outreach. Intent decays, so it should be scored with recency.

A workable first model needs no software: two scores out of five, one for fit and one for intent, and a rule that only high fit plus high intent passes to sales. High fit with low intent goes to nurture. Low fit with high intent gets a polite answer and a self serve route. That grid does ninety per cent of what an elaborate scoring system does.

The handover rules worth agreeing before the next campaign

• Response time. A stated maximum from lead creation to first contact attempt, measured in the CRM. Speed of first contact changes outcomes more than almost anything else in the process.
• Attempts. How many contact attempts, by which channels, before a lead is set aside.
• Rejection reasons. A fixed list that sales must choose from when returning a lead: wrong size, wrong country, no budget, no need, duplicate, bad data. A rejection with no reason teaches marketing nothing.
• Recycling. Where a rejected lead goes, and what has to change before it comes back.
• Review. One monthly meeting that looks at rejection reasons and adjusts the criteria rather than blaming the channel.

Counting leads without inflating the number

Lead volume is the easiest marketing number to flatter, so agree the counting rules at the same time as the definitions.

• Deduplicate by email and company, and count a person once no matter how many forms they fill in.
• Exclude your own staff, suppliers, students and job applicants.
• Count a lead in the month its first interest signal arrived, not when sales got around to it.
• Report volume and acceptance rate side by side. Volume alone rewards whoever lowers the bar.
• Report cost per qualified lead rather than cost per lead, and connect it to acquisition cost. Our page on CAC and the six metrics it gets confused with covers the relationships between them.

This page covers the meaning of the word and the stages around it. For how businesses actually generate leads in practice, see our page on how lead generation works.

What gets asked about leads in marketing

What is a lead in simple words?

Someone who might buy from you, whose details you have, and who has shown some interest. Nothing more complicated than that.

What is the difference between a lead and a prospect?

A lead has shown interest. A prospect is a lead that has been checked against your criteria and judged a plausible buyer. Lead comes first, prospect second.

What does MQL mean?

Marketing qualified lead: a lead that matches your target profile and has shown buying intent, measured against criteria that marketing and sales agreed in writing. The agreement is the important half, not the abbreviation.

Are leads bought from a list real leads?

A purchased list gives you identity and contact details and no interest signal, so it is a target list rather than leads. Treat it as outbound prospecting, check the consent position in your market before using it, and measure it against outbound benchmarks rather than against inbound lead numbers.

How many leads do we need?

Work backwards from revenue. Target revenue divided by average deal size gives the deals needed. Divide by your close rate for the opportunities needed, then by your qualification rate for the leads. That calculation gives a target with arithmetic behind it instead of a number picked in a meeting.

Who owns lead quality?

Both teams, through the shared definition. Marketing owns volume against the criteria, sales owns what happens after acceptance, and the criteria themselves are revised together once a month.

Where to go from here

• How lead generation actually works
• Pay per lead agencies and the clauses to settle first
• Sixty marketing terms in plain language
• Customer acquisition cost, worked

The lead that arrives with no source attached

Your handover rules assume a lead has a source: a form, a campaign, a referral. Some now arrive saying only that they were told to speak to you, and the source field reads direct.

One reason is an assistant recommending your company in a conversation your analytics never saw. Add a free text question to the form asking how they found you, and ask an assistant your buying question to see what it says. AI Knows Us logs the answers, which helps you interpret leads whose source field stays empty.