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How to write a business case study

A business case study tells the true story of one customer: the problem they faced, what they did with your product or service, and the measurable result. The customer is the hero; your company is the guide that helped them get there.

THE CASE STUDY ARC1Beforethe customer’s situation2Challengethe problem that forced a change3Solutionwhat they did, with your help4Resultsmeasurable change, with datesThe story falls to the challenge, then rises to the result.
Short answer

A case study follows one customer through four beats: the situation before, the problem that forced a change, what they did with your help, and the measurable result. Use the customer’s own words, real numbers with a time frame, and keep it to one page.

Four formats compared

The same customer story can be told at four lengths. Write the one-page version first; the others are cut from it.

FormatLengthWhere it is usedWhat to keep
Full case study600 to 900 wordsWebsite, sales follow-upAll four beats, two quotes, three numbers
One-pager250 to 350 wordsPDF leave-behind, proposalsProblem, result, one quote
Snapshot40 to 60 wordsSlides, landing pagesThe result number and the customer name
Quote card1 to 2 sentencesSocial posts, email signaturesThe customer’s strongest line, with their name and role

Inside a proposal, a one-pager sits best after your pricing, as proof the price is worth it. See the business proposal guide for where it fits.

A complete one-page case study

The layout readers expect: a headline with the result, a results strip, then the story in four short sections and a pull quote.

Case study · Fieldhouse Coffee How Fieldhouse Coffee grew mobile orders by 62% in six months
+62% mobile orders in six months
58 sec average time to order, down from 4 minutes
£140k extra online sales in year one
The customer Fieldhouse Coffee runs nine cafés across Bristol and Bath, serving about 6,000 customers a day.
The challenge Most customers browsed on their phones, but the old ordering page took four minutes to complete. Almost half gave up at payment, and staff spent mornings taking orders by phone.
The solution Northlight Studio rebuilt the site around ordering in under a minute, with saved favourites and click-and-collect at every café. Two cafés piloted it for a fortnight before launch.
The results Within six months, mobile orders rose 62% and phone orders fell by two-thirds, freeing staff for the counter. Online sales added £140,000 in the first year.
“Customers order from the bus now. The new site paid for itself by March.” Sarah Lin, Operations Director, Fieldhouse Coffee
How to write a business case study, step by step →

The customer interview

Every case study starts with a 30-minute conversation. Ask open questions in the same order as the story, and record the call (with permission) so quotes are exact.

Before
“Tell me about your business and your role.”“How did ordering work before?”
The challenge
“What made you look for a change?”“What was it costing you in time or money?”
The solution
“Why did you choose us?”“What was the rollout like for your team?”
The results
“What has changed since?”“What would you tell a business considering it?”

Framing the numbers

A metric persuades when the reader can picture it. Give each result a baseline, a time frame and, where possible, its value to the business.

FrameWritten asWhat it adds
BaselineOrder time fell from 4 minutes to 58 seconds.The starting point makes the change measurable.
Time frameMobile orders rose 62% in six months.Shows the speed of the result.
MoneyOnline sales added £140,000 in year one.Translates the result into business value.
Human scaleStaff now spend mornings at the counter, not on the phone.Lets readers picture the difference.
ComparisonPhone orders fell by two-thirds.A fraction is easier to grasp than a raw count.

Ask the customer to approve every figure and quote before publishing. Related: customer case study template in reports and summaries.

Headlines that work

The headline is the result, not the customer’s name. Readers decide in the first line whether the story is relevant to them.

Brightway Logistics case study→How Brightway cut late deliveries by 38% in six months
A partnership story→From 3 days to 4 hours: faster invoicing at Norden Foods
Customer success: Alba Clinics→Alba Clinics filled 92% of cancelled slots with automatic reminders

From interview to published

  1. Week 1Ask and agreeAsk a happy customer, agree what they are comfortable sharing, and book a 30-minute call.
  2. Week 1InterviewRecord the call with permission. Ask for numbers and for the moment they knew it was working.
  3. Week 2DraftWrite the four beats from the transcript. Keep their words, cut your adjectives.
  4. Week 2Customer reviewSend the draft for approval. Ask them to check every number and quote.
  5. Week 3Publish and reusePublish the full version, then cut the one-pager, snapshot and quote card from it.

Approval matters: a customer who signs off the draft is far more likely to agree to be a reference later. The customer case study template includes an approval email you can send.

The full guide

1 article · 16 min readHow to Write a Business Case Study, Step by StepStructure, interview scripts, metric framing and templates. Read the guide →

Guides on case studies

1 guide · newest first
How to Write a Business Case Study Step by Step
How to Write a Business Case Study Step by StepStep-by-step guide to writing business case studies that sell: structure, interview scripts, metric framing, templates, and common failure modes.Apr 23, 2026 · 16 min read