How to write a good case study (that people will actually read)

Ana Rabaça
May 28
4 min read

Updated: Jun 17

Most B2B case studies are boring, filled with long paragraphs, vague results and a headline that reads like a file name. Which is a shame because case studies are one of the most powerful sales tools you can create.

A good case study builds trust. It shows proof and helps future customers see themselves in the story. But it only works if it's actually worth reading.

Let's see how you can write a good case study. One that's clear, believable, and built to help your sales team close.

tablet with a case study, one pager, by Estoria Lab, on a smoky pink and mint background

Why case studies matter

If you're in B2B sales or marketing, case studies aren't optional. And research backs this up:

73% of B2B buyers use case studies to research their purchases
Case studies that include real stories and testimonials help convert at a higher rate than other content types because they offer real-world proof.
In high-consideration sales cycles, case studies are often forwarded internally, influencing multiple decision-makers.

And yet, they're often treated as an afterthought. The good news? With the right format and mindset, you can create case studies that work for your team.

What's wrong with most case studies

They're too long
Being 100% real, your reader is most likely just skimming your case study, not studying it. Yet so many case studies drag on for 1500+ words with no clear arc. And the length isn't even the problem; the lack of clarity is.
They're too vague
"Client saw improvements". This, in itself, doesn't mean anything. A good case study shows exactly what changed, by how much, and what that meant in the real world. Remember, vagueness kills trust. So, instead of going with "we help them improve their process", opt for "after implementing our tool, their optimized process led to an increase of 25% in client satisfaction within two months".
They're too self-centered
If your case study is all about you and how great you are, you're doing it wrong. Customers care about their own problems, not your achievements and accolades. Good case studies show the customer as the hero of the story.
There's no story arc
Storytelling isn't fluff. It's deeply connected to how people process information, and if you skip over the problem and jump straight to your solution, you lose all the narrative tension. And that's the part that makes people care.
They're written like press releases
Overuse of jargon, buzzwords, robotic language that strips out any personality and authenticity. Case studies should feel personal, like one professional sharing a success story with another during a chat.

What makes a good case study

Here's the structure we recommend and use at Estoria Lab. It's not rocket science, but it works.

Start with a headline that has a clear takeaway
Don't title your case study "Company X Case Study". That tells us nothing. Instead, write a headline with a real result:
- "How we helped X Company increase demo conversions by 3x in 90 days"
- "How this X Company cut churn in half without hiring a new team"
Tip: use a number, a result, and a short time frame.
Problem - Solution - Result
This is the core structure we use for all client case studies:
- Problem / Challenge - set the scene. What wasn't working? What was at stake? (Make sure to add some urgency and make your reader curious.)
- Solution - explain what you did, briefly and clearly. Keep the focus on the decisions that mattered. The reader doesn't need to know every single step, no need to explain the process in detail, they want the thinking behind your choices.
- Results - quantify the change. Being clear and showing data will improve the credibility of the case study, even better if you have a testimonial you can share.

4 Tips to make your case study actually readable

Keep paragraphs short, with no walls of text. You're not writing a novel, so 2-3 lines per paragraph is more than enough.
Use subheadings to break your text. By having clear subheadings throughout your case study, you will make it easy for readers to jump to the parts they care about.
Make the key wins and outcomes easy to spot with bold text.
Use your clients' real words; rewriting to make them sound more professional is a mistake.

Some case study formats that work (and when to use them)

One-pager

Best used in sales follow-ups, outbound emails, and pitch decks. One-pagers are quick to digest and have a high impact. Unless you have a good reason to go longer, this should be the default format.

Slide Deck

Best for larger deals, enterprise sales, or longer sales cycles. This format is ideal when you're dealing with multiple decision-makers who need fast overviews of materials before approving the deal.

Blog-style hybrid

Best used for SEO, brand building, and demand gen. This is usually a long-form format with high emphasis on storytelling, with rich details, quotes, and context.