What is an ICP, and why you should write yours down

Most people who struggle with outreach don’t have a writing problem. They have a “who” problem.

They send the same email to anyone who looks roughly right, get a handful of polite replies and a lot of silence, and decide cold email doesn’t work. It usually does work. It just works much better when you know exactly who you’re writing to and why they’d care.

That’s what an ideal customer profile is for.

What an ICP actually is

An ICP is a short description of the businesses you most want as customers. Not everyone who could buy from you. The ones who buy quickly, stay, pay on time and tell other people about you.

A good one answers six questions:

What kind of business is it? Sector, size, location, legal form.
Who makes the decision? The job title of the person who says yes.
What do they care about? The problems that keep coming up.
When is a good time? The signals that tell you they need you now.
Where do you find them? The searches and lists that turn up more of them.
Who do you leave out? The ones who look right but never buy.

If you can answer those in plain English, you have an ICP.

Why write it down

You probably have most of this in your head already. Writing it down does three things.

It makes you pick. “Small businesses in the South West” isn’t an ICP. “Limited companies with 10 to 50 staff, opening a second site, where the operations manager makes the call” is. Once it’s on paper, the vague bits stand out.

It makes your research faster. Every search you run in Apollo, Companies House or a job board comes straight from the ICP. You stop scrolling and start filtering.

And it makes AI tools genuinely useful. Paste a written ICP into Claude or Copilot and you can ask it to suggest searches, score a list of companies, or draft a first email that fits. Without the ICP, you get generic output. With it, you get something close to what you’d have written yourself.

How to write one in an hour

Start from your best three customers. Not the biggest, the best. Write down what they have in common: size, sector, who you dealt with, what made them get in touch, and what happened just before they did.

Then do the same for your worst two. That gives you the “leave out” list.

Finally, write the offer you’d lead with. One specific thing, easy to say yes to. A free review, a fixed quote, a short call with something useful at the end.

If you’d rather not start from a blank page, use one of our free templates below, or build your own with the ICP generator.

A note on the rules

In the UK, you can email limited companies, LLPs and public bodies without asking first, as long as you say who you are and make it easy to opt out. Sole traders and ordinary partnerships are treated as individuals, so you need their consent before you email them. Named contacts are still personal data under UK GDPR, so keep only what you need and link to your privacy notice.

Build that into your ICP from the start and you won’t have to untangle it later. This isn’t legal advice, and the ICO is updating its guidance after the Data (Use and Access) Act 2025, so check the latest before you send.

Free ICP templates

Each one is a plain text file you can edit and paste straight into Claude, Copilot or ChatGPT.

Or build your own ICP in a few minutes.

Once you know who you’re writing to, Waving helps you send plain text emails from your own domain, one at a time, with you approving every one.