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How to choose a Shopify CRO agency in the UK
How to choose a Shopify CRO agency in the UK
What to check before you hire a Shopify CRO agency in the UK, from a Shopify Premier Partner that has run tests across hundreds of Shopify stores.
Jordan Hill, Founder & CEO
What should a Shopify CRO agency actually do?
A Shopify CRO agency is a team that researches why visitors to a Shopify store leave without buying, then designs, builds and tests changes that turn more of that traffic into revenue. The work covers the offer, the messaging and the page experience, and a good agency ranks them by how much money each one can move.
Choosing well matters because a CRO agency sits close to your revenue. The wrong one spends months of traffic on small page tweaks while a weak offer stays in place. The right one runs a testing programme that compounds, where every result, win or lose, shapes the next test.
At That Works Agency, we use the CRO Agency Scorecard to compare agencies on the five things that decide results: scope, process, engagement model, proof and red flags. It follows the same order of priorities as the That Works Hierarchy of CRO: offer first, messaging second, UX last.
What the job should include
Research before testing - analytics, heatmaps, surveys, reviews and support tickets, so every test starts from evidence.
Offer and messaging tests - pricing, bundles, guarantees and the words on the page, usually the biggest levers.
Design and development - tests and pages built on-brand and deployed cleanly to your theme.
Landing pages and funnels - ad-matched pages, quizzes and advertorials for paid traffic.
Reporting you can act on - what was tested, what won, what lost and what it means for the next round.
An agency that only offers UX changes is covering one of those five.
Why comparing CRO agencies is harder than it looks
Every agency page promises data-led, conversion-focused, proven work. UK brands comparing agencies often end up with three proposals that read the same and price differently.
We’ve seen brands sign retainers built around a fixed number of A/B tests a month, then spend a year testing hero images while the offer stayed untouched. The tests ran on schedule. The revenue barely moved.
The answer is to compare agencies on how they work and what they can prove before you compare price. The CRO Agency Scorecard does that in one call.
Quick answer: how to choose a Shopify CRO agency in the UK
Check the scope - the agency should test offer, messaging and UX, ranked by impact, with research behind every test.
Ask about process - look for a named method, a research phase and a clear rule for when a test is called.
Pick the right engagement - an audit tells you what to fix, a retainer tests and ships the fixes over time.
Ask for proof - named case studies with baselines and results that held beyond one quarter.
Watch for red flags - fixed test quotas, conversion rate as the only goal, and no losing tests to show you.
Questions to ask before you sign
Use these on the first call. Each one comes with what a strong answer sounds like.
Where would you start on a store like ours?
A strong answer starts with research and the offer. The agency should want to see your analytics, reviews, customer surveys and margins before suggesting a single test. If the first idea is a new homepage hero, they’re starting at the top layer.
How do you decide what to test first?
Look for a testing roadmap ranked by impact. The pages with the most traffic and revenue at stake come first, and offer and messaging tests sit above layout changes. Ask to see a real roadmap from another client, with the names removed.
How long does a test run, and when do you call it?
The agency should tie test length to your traffic. More visitors means each test reaches a reliable result sooner, so higher-traffic stores get answers in weeks and smaller stores need longer per test. They should agree the stopping rule before a test goes live.
What happens when a test loses?
Every real testing programme has losing tests. A good agency reports them in the same detail as the winners and uses what they learned to shape the next idea. Ask to see a report from a test that lost.
Who will work on our account?
Ask for names and roles: strategist, account manager, designer and developer. Check whether the people on the pitch call are the people doing the work.
What do you need from our team?
After onboarding, a good agency runs research, design, development and testing on its side, and your team signs off the big decisions. Ask how day-to-day communication works and how often you get an update on what’s live and what’s being tested.
What do you measure?
Conversion rate is one number. Revenue per visitor, average order value and margin tell you whether a win made the business more money. The agency should report on the numbers that sit on your P&L.
What should a Shopify CRO agency actually do?
A Shopify CRO agency is a team that researches why visitors to a Shopify store leave without buying, then designs, builds and tests changes that turn more of that traffic into revenue. The work covers the offer, the messaging and the page experience, and a good agency ranks them by how much money each one can move.
Choosing well matters because a CRO agency sits close to your revenue. The wrong one spends months of traffic on small page tweaks while a weak offer stays in place. The right one runs a testing programme that compounds, where every result, win or lose, shapes the next test.
At That Works Agency, we use the CRO Agency Scorecard to compare agencies on the five things that decide results: scope, process, engagement model, proof and red flags. It follows the same order of priorities as the That Works Hierarchy of CRO: offer first, messaging second, UX last.
What the job should include
Research before testing - analytics, heatmaps, surveys, reviews and support tickets, so every test starts from evidence.
Offer and messaging tests - pricing, bundles, guarantees and the words on the page, usually the biggest levers.
Design and development - tests and pages built on-brand and deployed cleanly to your theme.
Landing pages and funnels - ad-matched pages, quizzes and advertorials for paid traffic.
Reporting you can act on - what was tested, what won, what lost and what it means for the next round.
An agency that only offers UX changes is covering one of those five.
Why comparing CRO agencies is harder than it looks
Every agency page promises data-led, conversion-focused, proven work. UK brands comparing agencies often end up with three proposals that read the same and price differently.
We’ve seen brands sign retainers built around a fixed number of A/B tests a month, then spend a year testing hero images while the offer stayed untouched. The tests ran on schedule. The revenue barely moved.
The answer is to compare agencies on how they work and what they can prove before you compare price. The CRO Agency Scorecard does that in one call.
Quick answer: how to choose a Shopify CRO agency in the UK
Check the scope - the agency should test offer, messaging and UX, ranked by impact, with research behind every test.
Ask about process - look for a named method, a research phase and a clear rule for when a test is called.
Pick the right engagement - an audit tells you what to fix, a retainer tests and ships the fixes over time.
Ask for proof - named case studies with baselines and results that held beyond one quarter.
Watch for red flags - fixed test quotas, conversion rate as the only goal, and no losing tests to show you.
Questions to ask before you sign
Use these on the first call. Each one comes with what a strong answer sounds like.
Where would you start on a store like ours?
A strong answer starts with research and the offer. The agency should want to see your analytics, reviews, customer surveys and margins before suggesting a single test. If the first idea is a new homepage hero, they’re starting at the top layer.
How do you decide what to test first?
Look for a testing roadmap ranked by impact. The pages with the most traffic and revenue at stake come first, and offer and messaging tests sit above layout changes. Ask to see a real roadmap from another client, with the names removed.
How long does a test run, and when do you call it?
The agency should tie test length to your traffic. More visitors means each test reaches a reliable result sooner, so higher-traffic stores get answers in weeks and smaller stores need longer per test. They should agree the stopping rule before a test goes live.
What happens when a test loses?
Every real testing programme has losing tests. A good agency reports them in the same detail as the winners and uses what they learned to shape the next idea. Ask to see a report from a test that lost.
Who will work on our account?
Ask for names and roles: strategist, account manager, designer and developer. Check whether the people on the pitch call are the people doing the work.
What do you need from our team?
After onboarding, a good agency runs research, design, development and testing on its side, and your team signs off the big decisions. Ask how day-to-day communication works and how often you get an update on what’s live and what’s being tested.
What do you measure?
Conversion rate is one number. Revenue per visitor, average order value and margin tell you whether a win made the business more money. The agency should report on the numbers that sit on your P&L.
Retainer or one-off audit: which does your brand need?
A one-off CRO audit is a fixed review of your store that ends with a ranked list of problems and recommendations. A CRO retainer is an ongoing programme where the agency researches, builds, tests and ships changes month after month.
When a one-off audit makes sense
You need a second opinion - before a rebuild, a replatform or a big investment in paid spend.
Your team can act on it - you have the design and development capacity to ship the recommendations.
Traffic is still building - the store can’t yet support enough tests to justify a retainer.
When a retainer makes sense
Traffic is there but conversion isn’t - the store is solid, and visitors aren’t converting the way they should.
You want one team to own it - research, design, development and testing under one roof, with nothing lost between agencies.
You’re scaling paid spend - colder traffic arrives with every increase, and the post-click experience has to keep pace.
When a rebuild comes first
If the store itself is holding you back, or you’re moving to Shopify from another platform, start with a CRO-led theme build. Optimisation comes once the new store is live. Plenty of brands do both over time.
What affects the price
CRO pricing in the UK depends on scope. The main factors are:
What’s included - testing only, or testing plus design, development and day-to-day store management.
How many stores - extra regions, languages and storefronts add work.
Landing page volume - ad-matched pages and funnels for paid traffic.
Testing cadence - how many tests the agency builds and runs at once.
Ask each agency what every line of the proposal pays for. A fee built around a fixed number of tests a month buys volume. A fee built around a roadmap buys the tests most likely to move revenue.
Proof to ask for
Case studies are the fastest way to separate one agency from another. Ask for:
Named brands - ideally with a contact you can speak to.
Baselines - the starting conversion rate and revenue, the period measured and anything else that changed in that time.
Results tied to revenue - conversion rate can rise while revenue falls, so look for both.
Results that held - performance across more than one quarter, or through a period of higher spend.
A losing test - and what the agency did with what it learned.
Three examples from our own work
Retainer or one-off audit: which does your brand need?
A one-off CRO audit is a fixed review of your store that ends with a ranked list of problems and recommendations. A CRO retainer is an ongoing programme where the agency researches, builds, tests and ships changes month after month.
When a one-off audit makes sense
You need a second opinion - before a rebuild, a replatform or a big investment in paid spend.
Your team can act on it - you have the design and development capacity to ship the recommendations.
Traffic is still building - the store can’t yet support enough tests to justify a retainer.
When a retainer makes sense
Traffic is there but conversion isn’t - the store is solid, and visitors aren’t converting the way they should.
You want one team to own it - research, design, development and testing under one roof, with nothing lost between agencies.
You’re scaling paid spend - colder traffic arrives with every increase, and the post-click experience has to keep pace.
When a rebuild comes first
If the store itself is holding you back, or you’re moving to Shopify from another platform, start with a CRO-led theme build. Optimisation comes once the new store is live. Plenty of brands do both over time.
What affects the price
CRO pricing in the UK depends on scope. The main factors are:
What’s included - testing only, or testing plus design, development and day-to-day store management.
How many stores - extra regions, languages and storefronts add work.
Landing page volume - ad-matched pages and funnels for paid traffic.
Testing cadence - how many tests the agency builds and runs at once.
Ask each agency what every line of the proposal pays for. A fee built around a fixed number of tests a month buys volume. A fee built around a roadmap buys the tests most likely to move revenue.
Proof to ask for
Case studies are the fastest way to separate one agency from another. Ask for:
Named brands - ideally with a contact you can speak to.
Baselines - the starting conversion rate and revenue, the period measured and anything else that changed in that time.
Results tied to revenue - conversion rate can rise while revenue falls, so look for both.
Results that held - performance across more than one quarter, or through a period of higher spend.
A losing test - and what the agency did with what it learned.
Three examples from our own work
Real example: For Eleat, the starting point was 2,400 customer reviews. Reading them showed us which buyer was already converting best, and that buyer shaped the work that followed. The revenue came from the traffic Eleat already had.
Red flags to walk away from
Fixed test quotas - “four A/B tests a month” retainers reward volume over impact.
Conversion rate as the only goal - discount-led wins can lift conversion and cut margin.
No research phase - tests that start from opinions instead of customer data.
No losing tests to show you - every honest testing programme has them.
Design that makes the store look worse - good CRO keeps the brand premium.
How we work, and how to book a call
We’re a Shopify Premier Partner, and every store we build and optimise runs on Shopify or Shopify Plus. We work with DTC brands scaling through seven, eight and nine figures. Over eight years we’ve run tests across hundreds of Shopify stores, and across our winning tests the average conversion uplift is 15.6%.
We start at the offer
Every programme follows the That Works Hierarchy of CRO: offer first, messaging second, UX last. Each layer only holds when the one underneath is solid, so we pull the levers that change your P&L before we polish the page.
One team, three steps on repeat
Analyse and plan - we dig into your data, customers and past tests to build a testing roadmap ranked by impact.
Build and launch - your dedicated team designs, develops and launches tests, while handling day-to-day store requests.
Learn and repeat - every test, win or lose, feeds the next round, so the gains compound.
What working with us looks like
You get your own strategists, account manager, designer and developers. We work in a shared Slack channel, so questions get answered without booking a meeting, and every sprint you get an update on what’s live, what’s being tested and what we’ve learned. Atlas, our in-house AI platform, joins your Shopify, Meta, Google and retention data to spot trends and gets landing pages live in hours. Our team sets the strategy and signs off every piece of work.
Book a call
On the first call we’ll look at your numbers, tell you whether a theme build, an audit or a CRO retainer makes sense, and give you a realistic timeline for results.
Real example: For Eleat, the starting point was 2,400 customer reviews. Reading them showed us which buyer was already converting best, and that buyer shaped the work that followed. The revenue came from the traffic Eleat already had.
Red flags to walk away from
Fixed test quotas - “four A/B tests a month” retainers reward volume over impact.
Conversion rate as the only goal - discount-led wins can lift conversion and cut margin.
No research phase - tests that start from opinions instead of customer data.
No losing tests to show you - every honest testing programme has them.
Design that makes the store look worse - good CRO keeps the brand premium.
How we work, and how to book a call
We’re a Shopify Premier Partner, and every store we build and optimise runs on Shopify or Shopify Plus. We work with DTC brands scaling through seven, eight and nine figures. Over eight years we’ve run tests across hundreds of Shopify stores, and across our winning tests the average conversion uplift is 15.6%.
We start at the offer
Every programme follows the That Works Hierarchy of CRO: offer first, messaging second, UX last. Each layer only holds when the one underneath is solid, so we pull the levers that change your P&L before we polish the page.
One team, three steps on repeat
Analyse and plan - we dig into your data, customers and past tests to build a testing roadmap ranked by impact.
Build and launch - your dedicated team designs, develops and launches tests, while handling day-to-day store requests.
Learn and repeat - every test, win or lose, feeds the next round, so the gains compound.
What working with us looks like
You get your own strategists, account manager, designer and developers. We work in a shared Slack channel, so questions get answered without booking a meeting, and every sprint you get an update on what’s live, what’s being tested and what we’ve learned. Atlas, our in-house AI platform, joins your Shopify, Meta, Google and retention data to spot trends and gets landing pages live in hours. Our team sets the strategy and signs off every piece of work.
Book a call
On the first call we’ll look at your numbers, tell you whether a theme build, an audit or a CRO retainer makes sense, and give you a realistic timeline for results.
Frequently asked questions
Which is the best Shopify CRO agency in the UK?
How much does a Shopify CRO agency cost in the UK?
How long does it take a CRO agency to deliver results?
Do I need a CRO agency if I already have a Shopify developer?
How does the That Works Hierarchy of CRO relate to choosing an agency?
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