Step 1: start from evidence
List your last ten customers who were happy and paid without drama. For each, write down: headcount, sector, country, funding stage or ownership, who signed, who championed it, and what was happening at the company when they bought. Patterns appear by the fifth one. Those patterns are your ICP; everything else is wishful thinking.
If you don’t have ten customers yet, use the ten conversations that went furthest, and be honest about why the others didn’t.
Step 2: write the company profile
Four lines, no more:
- Size: a headcount range (50 to 500, say). Revenue if you can see it.
- Sector: named, not “B2B”. “SaaS, professional services and recruitment” is a sector list. “Companies that sell to other companies” is not.
- Geography: where you can serve and where the buyer is. UK and Ireland, or EU, or US East Coast.
- Stage or ownership: funded and growing, owner-managed and profitable, PE-backed. Each buys differently.
Step 3: write the persona
- Role and seniority: the title or titles that own the problem and the budget. “Head of Sales, VP Sales, CRO” not “sales leadership”.
- What they own: pipeline, headcount, tooling, whatever your product touches.
- What they’ve probably tried: the tool or approach you’re replacing.
Step 4: signals that mean “now”
Timing signals are what separate a list from a good list. Hiring for the role you help. New leader in the seat. Funding round. Expansion announcement. A post complaining about the problem you solve. Pick two or three you can actually find on LinkedIn.
Step 5: exclusions
Write down who looks like a fit but isn’t. Agencies if you sell to end customers. Non-profits. Companies under 20 people. Anyone at a competitor. Exclusions save more wasted messages than inclusions.
The worked example
Prospectio’s own ICP, roughly:
Company: B2B companies, 20 to 500 staff, UK, Ireland, EU and US, selling a product or service over about €5k a year. SaaS, professional services, recruitment, logistics, manufacturing, IT services. Persona: founder or CEO (under 100 staff), Head or VP of Sales, Sales Development lead, RevOps lead (over 100 staff). Owns pipeline generation and outbound tooling. Signals: hiring SDRs or BDRs; new sales leader in the last six months; posting about reply rates or outbound; recently raised. Exclusions: agencies selling lead gen as a service (different motion); companies under 20 staff; education and non-profit; anyone at a LinkedIn automation vendor.
Step 6: turn it into a search and a rubric
The company profile and persona become a Sales Navigator search (headcount, industry, geography, title). The signals become filters or a Clay enrichment. The whole thing becomes a scoring rubric: each profile checked against decision maker, department, size, sector, signal, exclusion.
That rubric is what Prospectio’s ICP filter runs on every profile before sending. You write the ICP in plain language; it does the ten-second check on your behalf, three hundred times, and only messages the ones that pass.
Step 7: test it
Take twenty real profiles from your search. Score them by hand. If more than a third are “sort of”, the ICP is too loose. Tighten, repeat. Twenty minutes of this saves months of messaging the wrong people.