"Cost of agency" is a search people type with a proposal open in the other tab. The proposal has a number on it. What it does not have is the context to judge the number, or the costs that sit outside it. Both are below.
Direct answer: In the UK an ecommerce or Shopify growth agency typically charges £750 to £2,000 a month for a light retainer, £2,500 to £6,000 for a proper one with a named operator, and £6,000 to £15,000 or more at Plus scale, fees only, before ad spend. Percentage-of-spend deals run 10 to 20 percent. Hourly rates sit around £75 to £150 for delivery and £150 to £250 for senior people. The true cost adds your own hours managing them, which is the overhead nobody quotes.
Questions that bring people here
The four ways agencies price
| Model | How it reads | Who carries the risk |
|---|---|---|
| Flat monthly retainer | Fixed fee, scope in the statement of work | You, if scope is vague. Them, if your spend grows and the fee does not |
| Percentage of ad spend | 10 to 20 percent, sometimes tiered down | You. They earn more when you spend more, including when you should not |
| Fee plus percentage | A base fee that covers the floor, a percentage that scales | Shared, if the base is honest. Padded twice if it is not |
| Project fee | Fixed quote for a defined build or migration | Them, until the first change request |
The question to ask any percentage-of-spend agency is what happens in the month your best sellers run thin and the right decision is to halve the budget. A good operator answers immediately. A weak one changes the subject. The pricing models are unpacked further in Shopify retainer cost.
Retainer bands, by what you are buying
| What you are buying | Typical UK monthly (fees only) | Notes |
|---|---|---|
| Light growth retainer | £750 to £2,000 | Junior buyer plus a shared strategist, limited creative |
| Solid growth retainer | £2,500 to £6,000 | Named operator, weekly optimisation, a creative pipeline, real reporting |
| Plus-scale growth | £6,000 to £15,000 and beyond | Heavier SLAs, more stakeholders, multi-market |
| Support and maintenance | £400 to £1,500 | Fixes, small changes, updates, a response time |
| Development retainer | £2,000 to £8,000 | Reserved developer time for features and integrations |
Orientation, not a quote. Category, SKU count, number of markets and creative volume move these more than anything on this page. Development and support bands have their own guide: Shopify development and support retainers.
Project fees
Builds are quoted as projects rather than retainers, and the range is enormous because "a Shopify build" covers everything from a theme customisation to a replatform. Bands we see quoted in the UK: theme customisation and light design work from about £1,500 to £5,000; a custom theme build from £8,000 to £30,000; a Plus migration or replatform with integrations from £20,000 into six figures. A project quote without a written list of what is excluded is not a quote, it is an opening bid.
What "agency overhead" actually means
The phrase gets used two ways and it is worth separating them.
Inside the agency, overhead is every cost that is not billable delivery: sales, account management, office, software, management, the bench between clients. It is why an agency hourly rate is roughly two and a half to three times the salary cost of the person doing the work. That is not a scandal. It is how a services business survives. But it does mean a £4,000 retainer is buying perhaps £1,400 of somebody's actual time, and you should ask whose.
On your side, overhead is the time you spend making the agency effective: briefing, approving, answering Slack, chasing, re-explaining the product to the new account manager, reading the deck. For a founder that is commonly several hours a week. Price it at what your hour is worth and add it to the fee. Most agency comparisons leave it out, and it is often the difference between "worth it" and "not".
The real comparison: agency, hire, software, hybrid
An in-house ecommerce or paid social manager in the UK sits roughly at £40,000 to £65,000, more in London and for real seniority, plus employer costs of roughly a fifth on top, plus tooling, plus the weeks they are away. Monthly, that lands in the same band as a solid retainer. The difference is shape, not price: a hire is dedicated attention with single-person risk, an agency is a bench with divided attention.
Software changes the shape again. It is cheap per month, it does not sleep, and it is bad at taste and at the messy strategic call. The pattern that works for a lot of brands is a hybrid: software runs the monitoring, the stock checks and the routine, staged for approval; a human, in-house or agency, owns the creative and the hard decisions, with fewer hours because the routine is handled. The three shapes are compared in agency vs software vs hiring a media buyer, and you can run the numbers for your own situation in the agency cost model, which includes your hours and the overhead, not just the fee.
The fee is the visible number. Your hours are the invisible one. Add them together before you decide the agency is expensive, or cheap.
Five things that quietly change the price
- Minimum term and notice. Three months minimum and thirty days notice is normal. Twelve months with ninety days notice means you are paying a quarter to leave.
- Who does the work. The pitch is given by the senior person. Ask who is in the ad account on a Tuesday.
- Meeting load. A weekly call and a monthly deck can eat a third of a small retainer's hours. Cap it and take the hours back as delivery.
- What is excluded. Dev, email, marketplaces, feed hygiene, additional stores. Each one is a separate fee if it is not named.
- Ad account ownership. Always yours. Grant access, never transfer. An agency that wants to own the account is pricing in your switching cost.
If you are comparing an agency against Ralph specifically, the honest version of that comparison, including where an agency still wins, is on Ralph vs a growth agency.
Questions people actually ask
How much does a Shopify agency charge per month?
For growth work in the UK, fees only: roughly £750 to £2,000 a month for a light arrangement, £2,500 to £6,000 for a solid retainer with a named operator, and £6,000 to £15,000 or more at Shopify Plus scale. Development and support retainers run on different bands, from a few hundred pounds for support to several thousand for reserved developer time.
What does agency overhead mean?
Two things, depending on who is speaking. Inside an agency, overhead is everything that is not billable delivery: sales, account management, office, tooling, management. It is why an hourly rate is roughly two and a half to three times the salary cost of the person doing the work. For the client, overhead is the time you spend briefing, reviewing, chasing and re-explaining, which never appears on the invoice.
Is a percentage of ad spend a fair agency fee?
It is common, usually 10 to 20 percent and sometimes tiered down as spend rises. The problem is the incentive: the agency earns more when you spend more, including in the month when the right call is to cut because stock collapsed. It is fair if there is a floor, a cap, and a written answer to what happens when spend should fall.
What is an ecommerce agency's hourly rate in the UK?
Commonly £75 to £150 an hour for delivery staff at small and mid-size agencies, £150 to £250 for senior strategists and specialists, and higher in London or at named agencies. A retainer divided by those rates tells you how many hours you are notionally buying.
Is an agency cheaper than hiring someone?
Often similar in cash and different in shape. An in-house ecommerce or paid social manager in the UK sits roughly at £40,000 to £65,000 plus employer costs, which lands in the same monthly band as a solid retainer. A hire gives you dedicated attention and single-person risk. An agency gives you a bench and divided attention.
How do I cut agency cost without losing the work?
Cap meeting and reporting hours in the contract and ask for the time back as delivery. Move the monitoring and the routine into software or a checklist so the agency's hours go on decisions and creative. And name what is out of scope so the fee stops growing by accident.
cost of agency
In the UK, an ecommerce growth agency typically charges £750 to £2,000 a month for a light retainer, £2,500 to £6,000 for a proper one with a named operator, and £6,000 to £15,000 or more at Shopify Plus scale, fees only. Percentage-of-spend deals run 10 to 20 percent. Add your own hours managing them.
agency overhead
Inside an agency, overhead is everything that is not billable delivery, which is why an hourly rate is roughly two and a half to three times the salary cost of the person doing the work. On your side, overhead is the hours you spend briefing, approving and chasing, which never appear on the invoice.
If the retainer is the problem: Ralph does the routine half of a retainer every night from £99 a month: watching stock against spend and drafting the next package. Keep your humans for taste and strategy. See Ralph · What an agency costs · Docs