Most agency pricing debates end up in the same place: a heated Twitter thread where retainer advocates call project workers feast-and-famine addicts, and project-focused agencies accuse retainer shops of overcharging for vague ongoing work nobody can measure. Both sides are partly right — and both are missing the point.
The question isn’t “which model is better?” It’s “which model is better for this type of work, with this type of client, at this stage of the relationship?” Answered correctly, that question means most mature agencies end up running both models simultaneously, applied deliberately to different parts of their revenue. This article explains the real economics of each, where each breaks down, and how to structure a pricing model that works for an agency of 5–15 people in the UK market today.
The Honest Economics of Each Model
Before discussing when to use each, it’s worth being clear-eyed about what the numbers actually look like in practice — not the sales pitch version.
Project pricing looks attractive because of the lump sums involved. A £25,000 website build lands in your bank account and feels like a win. What gets obscured is the true cost of acquiring that project: the sales meetings, the proposal writing, the pitch deck, the competitive tender process, the legal back-and-forth on the contract. A realistic business development cost for a contested £25,000 project at a mid-market agency is often £2,000–4,000 in staff time — before a single billable hour is logged. Add a typical 15–20% scope overrun and you’re looking at an effective margin considerably thinner than the headline rate implies.
Retainer pricing looks less dramatic month-to-month — £2,000 or £3,000 arriving on a direct debit doesn’t trigger the same dopamine hit as a big project invoice. But a £2,500/month retainer renewed for 18 months is £45,000 in revenue from a relationship that was sold once. The acquisition cost drops to near zero after the initial win. The team develops deep familiarity with the client’s business, which means less briefing time and fewer revision rounds. The effective hourly rate, properly calculated, is almost always higher on mature retainers than on equivalent-value projects.
£25,000
Typical website project — one sale, 3–6 months of work, then start again
£45,000
£2,500/month retainer held for 18 months — sold once, lower overhead throughout
There’s also a compounding effect on retainers that doesn’t exist with projects. A client retained for two years has been upsold, cross-sold, and deepened in scope — their retainer value typically grows by 20–40% over that period as the relationship matures and trust increases. That same project client might reappear once every two years if you’re lucky, unchanged in scope.
Where Project Pricing Still Wins
There’s a tendency in agency strategy circles to treat retainers as inherently superior and project work as a necessary evil to be phased out. This is wrong. Project pricing is genuinely the right model for a defined class of work, and forcing retainerisation onto those engagements creates problems for everyone.
Defined-scope, one-time deliverables. A brand identity, a new website, a platform migration, a campaign — these have a clear start, a clear finish, and a tangible output. Clients understand the project model intuitively for this kind of work. They’re mentally prepared to make a decision and commit a budget. Trying to sell a “brand development retainer” often creates confusion and sales friction where none need exist. Price the project, deliver it well, and use the relationship to open a retainer conversation afterwards.
New client relationships. A cold or warm prospect who hasn’t worked with you before is often hesitant to commit to monthly ongoing spend before they’ve seen your work. A well-scoped project — a discovery sprint, a technical audit, an initial campaign — is a low-friction way to start the relationship. Once they’ve seen how you operate, a retainer conversation is far easier. Many agencies formalise this as a “discovery project to retainer” pathway: a fixed-price initial engagement that explicitly leads into a monthly scope discussion.
Higher-margin specialist work. If your agency does something genuinely specialist — say, Shopify Plus migrations, complex technical SEO recovery, or bespoke web application development — the market will pay a significant premium for that expertise on a project basis. A specialist agency can charge £150–200/hour on a project engagement where a retainer equivalent would be anchored closer to £80–100. For high-skill, high-effort, time-limited work, projects can be more lucrative than retainers.
Clients with inherently variable or irregular needs. Some clients genuinely don’t need you every month. A B2B business that runs two major marketing campaigns per year, a professional services firm that refreshes its website every 18 months — these clients aren’t good retainer candidates. Forcing them into a monthly commitment will generate resentment and early cancellations. Better to serve them well on projects and maintain the relationship warmly between engagements.
Where Retainers Win — and Win Significantly
For ongoing, continuous-effort services, retainers aren’t just preferable — they’re structurally superior for both agency and client. The work never really “finishes,” so packaging it as a series of disconnected projects creates artificial complexity and misaligned incentives.
SEO and content marketing are the canonical retainer services. Google’s algorithm doesn’t wait for a project to end before rewarding or penalising a site. Content compounds over time. The relationship between what was published last quarter and what ranks this quarter is not linear or discrete. A client who receives a monthly SEO report and a content delivery under a retainer is far better served — and far more likely to see results — than one who buys an “SEO project” every six months.
Paid media management follows the same logic. Managing Google Ads or Meta campaigns is an ongoing optimisation exercise. Campaign performance degrades if not actively managed. Creative fatigue sets in. Bid strategies need adjusting. A project-based paid media engagement is almost an oxymoron — you can build the campaign as a project, but managing it should always be a retainer.
Website care and maintenance is underappreciated as a retainer opportunity. UK digital agencies typically manage dozens of WordPress and e-commerce sites. Those sites need plugin updates, security patches, performance monitoring, uptime checks, and SSL renewals. This is textbook retainer territory: recurring effort, predictable cost, high value to the client (site downtime is immediately painful), and easy to price and scope. A well-run agency can productise this as a “website care plan” at £150–500/month per site and deliver it largely systematically, with tools like Marque CRM’s built-in site monitoring flagging issues before clients notice them.
Analytics and reporting is the glue that makes any ongoing service relationship sticky. A client who receives a clear, consistent monthly performance report — even a simple two-page summary — is demonstrably more likely to remain on a retainer than one who doesn’t. The report isn’t just a communication tool; it’s a documented record of value delivered. When a client considers cancelling, they look back at the last 12 months of reports and either see the impact clearly or don’t. Make sure they do.
The Hybrid Model Most Successful Agencies Actually Use
The practical answer for most 5–15 person UK digital agencies isn’t “retainers or projects” — it’s a deliberate hybrid where the two models serve different roles in the same business. Understanding that structure is more useful than arguing for one model in the abstract.
Here’s how the most commercially well-run agencies typically structure it:
Projects as acquisition. New client relationships begin with a project. This could be a discovery phase, a site audit, a strategy sprint, or a build. The project is priced to be profitable in its own right — this isn’t a loss-leader. But its secondary purpose is to establish the relationship, demonstrate the agency’s quality, and create the conditions for a retainer conversation. Every project brief should include an explicit “what happens next” proposal, usually presented at project handover or sign-off.
Retainers as the core revenue engine. Ongoing services — SEO, content, paid media, maintenance, reporting — are packaged into tiered monthly retainers. These are the agency’s core recurring revenue, ideally representing 50–70% of total income for a stable business. They are sold proactively, managed rigorously, and renewed with care.
Projects as upsells into the retainer relationship. A long-standing SEO retainer client wants a new landing page. A maintenance retainer client wants a site redesign. A paid media client wants a new campaign creative suite. These are sold as projects on top of the existing retainer — separate scope, separate invoice, often at a slight premium because the relationship is already established and the briefing process is fast. This “retainer-plus-project” pattern is significantly more profitable than either model alone, because acquisition cost is zero and briefing time is minimal.
A realistic revenue split for a 10-person agency
Monthly retainers: 55% of revenue (predictable, lower margin effort)
Ad-hoc projects from retainer clients: 25% of revenue (high margin, low sales cost)
New project clients (pipeline): 20% of revenue (variable, higher acquisition cost, feeds future retainers)
This structure creates a flywheel: project clients become retainer clients, retainer clients generate high-margin project work, and some of that project work brings in new contacts who become project clients. An agency with this flywheel running well barely needs to do outbound sales after the first few years.
Pricing Each Model Correctly — Where Most Agencies Go Wrong
The economics above only hold if both models are priced correctly. The most common failure modes are different for each.
Project pricing mistakes: The cardinal sin is time-and-materials with a vague ceiling. “Roughly 60–80 hours at £85/hour” sounds like a project quote but behaves like an open-ended engagement. Without a fixed scope and price, scope creep is structurally inevitable. Good project pricing is fixed-price against a well-defined scope, with a change control process for anything outside it. That means writing detailed specifications before quoting — slower up front, but it protects margin throughout.
A second common mistake is undercharging for complexity. A bespoke e-commerce build on Shopify with custom integrations is not the same as a template-based build, and should not be priced within 30% of it. Map your internal complexity tiers (simple / standard / complex) and build them into your quote templates. The market will support the premium if your positioning is right.
Retainer pricing mistakes: Anchoring to hours is the most persistent problem. “£1,200/month for 15 hours” sounds reasonable, but it trains the client to think of you as a time resource and invites hour-counting. Better framing: “£1,200/month for [defined deliverables] — here’s exactly what we produce and when.” This positions you as a specialist with expertise, not a contractor with a timesheet.
Underpricing relative to the reliability premium is also common. A retainer has value beyond the raw hours delivered — the client gets predictable access to your team, guaranteed capacity, and continuity of knowledge. That’s worth a 15–25% premium over equivalent project rates. Most agencies don’t charge it, either from competitive anxiety or a failure to articulate it. Be explicit: “Part of the retainer rate reflects guaranteed monthly capacity. We turn away other work to keep your team slot available.”
Finally, not building in an annual uplift clause. Inflation is real. A retainer signed in 2022 at a 2022 price is quietly losing margin each year. Include a 3–5% annual uplift provision in your retainer contracts, linked to CPI or a fixed rate. Flag it clearly at signing so it isn’t a surprise. The alternative — renegotiating from scratch every year — is more disruptive and risks the relationship more than a pre-agreed small increase.
Managing Both Models Without Administrative Chaos
The practical challenge with running projects and retainers simultaneously is that they require different operational rhythms, different tracking, and different client communication. Agencies that try to manage both on spreadsheets, or mix them into a single generic project management tool, invariably find that one model gets managed well and the other suffers.
Projects need clear milestones, deadline tracking, and client sign-off gates. Without those, projects drift, scope creeps, and invoices get delayed. Retainers need monthly hours or deliverables tracking, recurring invoicing, and health monitoring at the account level — not just the deliverable level.
The key operational requirements for managing both cleanly:
- Time tracking per client and per engagement type — you need to know, for each retainer, whether you’re over or under the contracted hours. And for each project, whether you’re tracking against your estimate. Without this, you can’t price the next one accurately.
- Separate invoicing flows — retainers generate recurring invoices automatically; projects generate milestone or completion invoices. These shouldn’t be in the same queue or managed the same way.
- Client health visibility — a retainer client who is going quiet, missing calls, and not opening monthly reports is at risk of churn. A project client who is slow to provide feedback may be losing interest. You need a single view of relationship health across both model types.
- Contract and scope management — both projects and retainers should have signed documents defining scope. When a client asks for something outside scope, you need to reference that document quickly and confidently.
Marque CRM handles the full operational stack for both models in one place: retainer contracts, project milestones, time tracking, recurring and milestone invoicing, and client health scores that surface accounts worth a proactive call before they consider cancelling. Rather than toggling between a project tool, a time tracker, an invoicing tool, and a CRM, your team has a single view of every engagement — project or retainer. See the full feature set at marquecrm.com/features.html.
Making the Decision for Your Agency
If you’re reading this trying to decide whether to push harder on retainers, pivot to project pricing, or restructure how you use both, here’s a practical framework for making that call.
Look at your last 12 months of revenue by type. What percentage was recurring retainers, what percentage was project work from existing clients, and what percentage was new project wins? If retainers are below 30%, your business is more volatile than it needs to be. If they’re below 20% and you’ve been running for more than three years, something structural needs to change.
Identify your most profitable engagements. Pull your time-tracked data and calculate actual margin per client. You’ll almost certainly find that your most profitable work falls into one of two categories: long-standing retainer relationships where the team is efficient and the scope is tight, or high-value specialist projects where your expertise commanded a premium rate. Everything in the middle — commodity project work, vague retainers that keep drifting — is where margin is quietly bleeding away.
Match your pricing model to your service type systematically. Go through your service menu. For each service: is this something a client needs continuously, or is it episodic? If continuous (SEO, maintenance, paid media, reporting) — make it retainer-only and stop quoting it as a project. If episodic (brand, build, campaign) — price it as a project with a retainer upsell built into the proposal. Enforce this consistently rather than quoting each engagement ad hoc.
Fix your contracts before you fix your pricing. No pricing model — retainer or project — survives without a clear signed contract defining what is and isn’t included. If your current contracts are thin or inconsistently enforced, that’s the first fix, not the pricing model. A well-defined scope, documented in a signed contract, makes every pricing conversation cleaner and every scope change discussion more straightforward. Handling scope changes without losing money covers this in detail.
The agencies that get this right — a deliberate mix of project and retainer work, priced correctly, managed operationally — are the ones with stable growth, rational cash flow, and teams that aren’t constantly context-switching between a crisis delivery and a cold pitch. It’s not complicated. It requires discipline, clear systems, and the willingness to say no to work that doesn’t fit the model you’ve chosen. That last part is harder than any pricing spreadsheet.
For a deeper look at building the recurring revenue side of this equation, see The Agency Owner’s Complete Guide to Monthly Recurring Revenue, and for the profitability mechanics that underpin both models, How to Track Profitability Per Client.