How to write a customer case study people want to read

You've got a customer who's happy with what you do. Maybe they told you on a call, or renewed without a second thought. That's a story worth telling. This guide covers how to write a customer case study that people read to the end: how to pick the right customer, what to ask them on a short call, and how to shape their story around the problem, the fix and the result, in their own words.

If you've searched for how to write a case study, you'll have found plenty of advice for students. This one's for businesses. (Some people call it a client case study. Same thing.)

Why bother with a case study?

People thinking about buying from you want to know if you've helped somebody like them before. A case study answers that, with enough detail that the next customer can picture themselves in it.

Step 1: Pick the right customer

Your happiest customer isn't always the best pick. Look for someone who:

• Looks like the customers you want more of. A story about a big hospital group won't help much if you mostly sell to small clinics.
• Had a clear problem before they found you. "Things were a bit messy" is hard to write about. "We lost bookings every weekend because nobody answered the phone" is easy.
• Can tell you what changed. A number is great. A clear before and after is fine too.
• Is happy to be named. Named stories are easier to believe. If they'd rather stay anonymous, say so plainly.

Ask soon after a win, like a smooth launch or a renewal.

Step 2: Ask for a short call, and make it easy to say yes

Keep the request small. Here's a made-up example:

"Hi Priya, we loved hearing how the new booking page went. Could we turn it into a short case study? It's a 20-minute call. We'll write it up, and you'll approve every word before it goes live."

Then stick to that promise. Get their permission in writing, agree whether you can use their name, logo and any figures, and send them the final draft.

There are rules here too. In the UK, the ASA (the advertising regulator) says you need permission to use a testimonial and should keep proof that it's genuine. In the US, the FTC says an endorsement has to reflect the honest opinion of the person giving it, and you should be open about connections readers wouldn't expect, like the customer being a relative or an employee.

Step 3: What to ask your customer on the call

You don't need a long script. A 20 to 30 minute chat with a few open questions will do. Record the call (with their OK) so you can quote them exactly.

Before: the problem

• What was going on before you started with us?
• What was that costing you, in time, money or stress?
• What had you already tried?

The decision and the fix

• Why did you pick us over the other options?
• Did you have any worries before you started?
• What did the first few weeks look like?

After: the result

• What's different now?
• Can you put a number on that? (It's fine if they can't.)
• What would you tell someone who's where you were a year ago?

That last question tends to get you your best line. If an answer's vague, like "it's been great", ask for an example. "Great how? What happened last week?"

Step 4: Shape the story around the problem, the fix and the result

Here's a simple structure:

• A headline with the result. Say who the customer is and what changed. For example (made up): "How a 40-room hotel in Goa started getting more direct bookings".
• A short summary up top. Two or three lines for people who skim.
• The problem. What was going wrong, in specifics, in their words.
• The fix. What they did with you, step by step. Keep the customer as the hero.
• The result. What changed, and how they know. Only use numbers they've given you and agreed to share.
• What's next, plus a quote. Close with their advice to someone in their shoes.

Keep it in their words

Your customer's words will sound more believable than yours. If they said "we stopped dreading Monday mornings", use that, and don't polish it into "improved operational efficiency". Tidy up the ums, keep their voice and send every quote back for them to check. For the rest of the piece, our guide to keeping your brand voice consistent can help.

Here's a made-up example of what we mean:

Polished: "The platform has delivered significant improvements to our patient communication processes."

Their words: "Patients used to ring us three times to check their appointment. Now they get a text and that's it."

No numbers? That's fine

A clear before and after can be enough, like "our front desk used to spend Sunday evenings answering the same booking emails, and now they don't." Never round up or guess a figure. If the customer can't back it up, leave it out.

A few tips by sector

• SaaS and AI: skip the feature list. Talk about the job the customer needed done and what changed. A good B2B case study also helps your buyer explain the choice to their boss.
• Health-tech: be extra careful. Leave out details that could identify a patient, check every claim with the customer, and get sign-off from the right person on their side, like a clinical lead.
• Hospitality: mention the type of property, the season and the problem, like empty midweek rooms or a phone that never stopped ringing.

Where to use it

Put it on your website, share a shorter version on LinkedIn and send it to prospects who are on the fence. Just raised money? A customer story makes great proof for your funding announcement too.

Customer case study FAQ

How long should a customer case study be?

Short enough that a busy person finishes it. A summary at the top and a few brief sections suit most growing companies.

What should a case study include?

Who the customer is, the problem they had, why they chose you, what they did, what changed and a quote or two in their own words. And their permission, in writing.

How do you ask a customer to do a case study?

Ask soon after a win and keep it small. Tell them how long the call will take, that you'll do the writing, and that they'll approve it before it goes live.

Case study or testimonial: which one do you need?

A testimonial is a line or two of praise, handy next to a button. A case study tells the whole story, which helps when someone's weighing up a bigger decision. Your best testimonial is a good place to start.

Want us to write yours?

We can run the customer call and write the case study for you. You can book it as a single piece, or make customer stories a regular part of a monthly content retainer. Email hello@markivasolutions.com with a few lines about your business and the customer you've got in mind. We'll come back with a few questions or a clear quote.