How to Choose a Shopify Agency in the UK: 12 Questions That Expose Bad Ones

We are a Shopify agency, so treat this with the appropriate scepticism. But we also spend a lot of time inheriting stores from other agencies, and the failure modes are predictable enough that a buyer can screen for most of them in a single call. This is that screening list.

Before you talk to anyone: define the job

"We need a Shopify agency" is four different briefs: a build or migration (project), ongoing development (retainer), growth (paid media, email, CRO, SEO) or all of it (full-service). Agencies that are excellent at one are often mediocre at another. Write down which you need, what "success in 12 months" looks like in numbers, and the budget range. Agencies price against uncertainty; the clearer the brief, the better the proposal.

The 12 questions

1. "Who, specifically, will work on my account?"

The pitch team and the delivery team are frequently different people. Ask for names, roles and how many other accounts each person carries. A strategist on 15 accounts is not doing strategy.

2. "Show me a store you built two years ago. How is it performing now?"

Launch-day screenshots are easy. A store that still converts well after two years of the client's own changes is the real evidence. Ask to speak to that client.

3. "What was the conversion rate before and after, and how did you measure it?"

If the answer is a percentage without a baseline, a date range and a source (GA4? Shopify? which attribution?), it is marketing, not measurement. See our GA4 guide for what proper measurement looks like.

4. "What do you not do?"

An agency that says "everything" either subcontracts heavily or does several things badly. Good agencies have a clear edge and will tell you where they would bring in a partner.

5. "Which apps do you install by default, and why?"

Reveals whether they think about site speed and cost. Twenty apps on a default build is a red flag. So is a "preferred partner" list with undisclosed referral commissions — ask directly.

6. "Who owns the theme code, the ad accounts and the Klaviyo account?"

You should. All of it, from day one, in your name. Agencies that run ads from their own Business Manager or build on a theme they license to you are building leverage, not value.

7. "How do you handle a Shopify update that breaks something you built?"

Tests whether they use Online Store 2.0 patterns, avoid hacking core theme files, and have a support process rather than a new quote every time.

8. "Have you sold products yourselves?"

Not disqualifying if no, but agencies with operators tend to prioritise differently — margin, returns, stock, fulfilment. Our own team runs Memo Wholesale and works daily inside Sleepy, Deep Fresh and Midland Tissue; it changes what you notice.

9. "What is your pricing model, and what changes it?"

Fixed-price project, day rate, monthly retainer, percentage of ad spend, or performance-based. Each has incentives. Percentage of spend rewards spending; pure performance rewards short-term tactics. A fixed retainer with a clear scope and quarterly review is usually the least distorted.

10. "What happens in month one?"

A good answer is specific: audit, tracking fixed, quick wins shipped, roadmap agreed. A vague "onboarding and discovery" for 30 days at full rate is a cost, not a plan.

11. "Show me a report you send to a current client."

You want revenue, margin-aware metrics and decisions — not a dashboard of impressions. If the sample is all top-of-funnel vanity, that is what you will get.

12. "What would make you fire us as a client?"

Sounds odd, but it reveals how they think about fit. Agencies that will take anyone tend to keep anyone, and quality of attention drops accordingly.

Red flags in proposals

• Guaranteed rankings or ROAS. Nobody controls Google or Meta.
• Long lock-in with no exit. 3 months' notice on a rolling contract is reasonable; 12-month minimums for a retainer are not, unless it is a build with milestones.
• No mention of tracking or data. If measurement is not in the first month's plan, results will be argued about later.
• "Shopify Plus Partner" as the whole pitch. The badge is real but broadly held; it says little about growth capability.
• Templated case studies. If every case study reports "300% growth" with no baseline, timeframe or channel, treat them as decoration.

What UK Shopify agencies actually cost (2026)

Cheaper exists, usually offshore or template-based, and can be fine for simple stores. Above these ranges you are paying for enterprise process, which mid-market brands rarely need.

Structuring the engagement

• Milestone-based payments for builds (design sign-off, dev complete, launch, 30 days post-launch).
• A written scope with explicit exclusions; change requests priced separately and in writing.
• You own all accounts, code and content. Put it in the contract.
• A 90-day review point on retainers with the option to exit without penalty.
• Reporting cadence and format agreed up front.

The best agencies are slightly annoying in the sales process: they ask hard questions about your margins and say no to things. That is what you want on your side later.

Frequently asked questions

How much does a Shopify agency cost in the UK?

Development retainers typically run £1,000–£5,000/month, growth retainers £2,500–£10,000/month plus ad spend, and full builds or migrations £15,000–£60,000 for mid-size stores. Shopify Plus and B2B builds cost more.

Should I choose a Shopify Plus Partner agency?

The Plus Partner badge indicates experience with Plus merchants but is widely held. Judge on relevant case studies, the people who will work on your account, and how they measure results — not on the badge alone.

Is a specialist Shopify agency better than a general digital agency?

For Shopify stores, usually yes. Specialists know the platform's limits, the app ecosystem and the conversion patterns. General agencies can be strong on brand and creative but often build slower, heavier stores.

What should be in a Shopify agency contract?

Clear scope and exclusions, milestone payments, your ownership of all accounts and code, notice period (3 months on rolling retainers is reasonable), reporting cadence, and a defined process for change requests.