The UK Freelancer's Guide to Retainer Agreements: Predictable Income, Every Month

Tired of the feast-and-famine cycle? A retainer agreement gives you a guaranteed monthly income from clients who already trust your work. Here's how to pitch one, write one, invoice for one, and avoid the mistakes that sink most retainer deals.

What Is a Retainer — and Why It Beats Project-Based Work for Cash Flow

A retainer is a simple idea: a client pays you a fixed monthly fee in exchange for an agreed amount of your time or a set of recurring deliverables. Instead of scoping, quoting, and invoicing every individual project, you have a standing arrangement — predictable work, predictable income, every month.

For most UK freelancers, the difference between "earning well" and "actually sleeping at night" comes down to one thing: predictability. You might bill £5,000 one month and £800 the next. You might finish a big project on Friday and have nothing lined up for Monday. That uncertainty is the single biggest source of stress in freelancing — and retainers are the closest thing to a cure.

Here's what changes when you land even one retainer:

• Your base income is covered. If your monthly costs are £2,500 and you have a £3,000 retainer, you start every month in profit before you've opened your laptop.
• You stop saying yes to bad projects. When you're not desperate for the next invoice, you can afford to be selective — better clients, better rates, better work.
• Your invoicing gets simpler. One invoice, same amount, same date, every month. No more chasing fifteen different invoices with fifteen different payment terms.
• You can actually plan. Holidays. Equipment. Savings. All the things that are impossible when your income is a rollercoaster.

Two types of retainer

Before you pitch anything, you need to decide which model fits your work:

Both models work. The key is choosing the one that matches the nature of the work — and being explicit about which model you're offering. Ambiguity here is where retainer deals fall apart.

How to Pitch a Retainer to an Existing Client

The best retainer clients are not strangers. They're clients you've already worked with — people who trust your work, keep coming back, and would benefit from a more structured arrangement. Pitching a retainer to a brand-new client almost never works, because they haven't experienced your value yet.

When to pitch

Look for these signals that a client is ready for a retainer conversation:

• They've hired you for 2–3 separate projects. A pattern of repeat work is the strongest signal.
• They're sending you ad-hoc requests regularly. "Can you do a quick thing for us?" every few weeks means there's ongoing demand.
• They've said something like "we should make this more regular" — or "I wish we could just have you on call."
• They're a growing business. Growing companies need reliable support. They don't want to brief a new freelancer every month.

The worst time to pitch is after a rocky project or when the client is clearly shopping around. The best time is right after you've delivered something they loved — when your value is fresh and undeniable.

How to frame it

A retainer is not about what you want (predictable income). It's about what they get. When you pitch, frame it entirely around their benefits:

• Guaranteed availability. "You'll have priority access to my time — no waiting for a slot in my schedule."
• Simpler budgeting. "One fixed cost per month instead of scoping and quoting every request."
• Faster turnaround. "Because I'm already embedded in your brand, there's no ramp-up time for each task."
• Continuity. "You get consistency in quality and voice — no onboarding someone new every quarter."

The pitch email

Notice a few things about this email:

• It offers options. Two tiers gives the client a choice between "yes at this level" and "yes at that level" — rather than "yes or no."
• It mentions out-of-scope work. This sets the expectation from the start that the retainer has limits, preventing scope creep down the line.
• It's low-pressure. "No pressure" and "happy to keep things project-by-project" takes the awkwardness out. You're suggesting, not selling.

Offer tiers, not a single price

Giving the client two or three options is a pricing psychology technique that works remarkably well. Instead of evaluating whether to buy, the client evaluates which option to buy. Here's a framework:

Most clients will pick the middle option. That's by design. Price the middle tier at the level you actually want — and make the top tier aspirational but genuinely valuable for bigger clients.

What to Include in a UK Freelance Retainer Agreement

A retainer without a proper agreement is just a vague promise — and vague promises are how freelancers end up doing unlimited work for a fixed fee. Your retainer agreement doesn't need to be a 20-page legal document, but it does need to cover these essential clauses.

1. Scope of work

Define exactly what the retainer includes. Be specific. "Marketing support" is not a scope. "4 × 1,200-word blog posts per month, optimised for SEO, with one round of revisions per post" is a scope.

For hours-based retainers, state the number of hours and the types of work those hours cover. For deliverables-based retainers, list every deliverable, its specification, and what counts as "complete."

The exclusions matter just as much as the inclusions. If you're a web developer on retainer for "site maintenance," make clear that a full redesign isn't maintenance. If you're a copywriter, state that keyword research or CMS uploading isn't included unless specified. For more on writing airtight scope clauses, see our guide to freelance payment terms and contracts.

2. Hours or deliverables cap

The cap is your financial safety net. Without it, a retainer becomes "unlimited work for a fixed fee" — which is worse than project-based billing.

The 80% notification is important — it prevents disputes. The client is never surprised by an overage invoice because you warned them before it happened.

3. Payment schedule

Retainer invoices should be paid in advance. This is non-negotiable for cash flow protection. The client pays at the start of the month (or before); you do the work during the month.

That last sentence isn't just legal boilerplate — it's a real right you have as a UK freelancer. See our detailed breakdown of UK late payment law and use our late payment interest calculator to see what you can claim if a retainer payment is late.

4. Rollover policy

What happens to unused hours or deliverables? This is the clause that causes the most arguments — and the most financial damage — if you get it wrong.

Your options:

• No rollover (use it or lose it). Simplest. Protects your schedule. The client pays for your reserved availability, not just the hours they use. This is the approach most agencies take.
• Limited rollover. Up to 25% of unused hours roll into the next month only — they don't accumulate further. A fair compromise that gives clients some flexibility.
• Full rollover. Avoid this. It creates a growing backlog of owed work that can overwhelm your capacity in a single month.

5. Termination notice

Both you and the client need a way out. But you also need protection against a client cancelling halfway through a month you've already planned around.

Thirty days is standard. Some freelancers use 60 days for larger retainers — this gives you time to find replacement income. Never agree to "cancel anytime, effective immediately" — that defeats the entire purpose of a retainer.

6. Review clause

Retainers should be reviewed periodically — at minimum, annually. This gives you a natural moment to adjust the scope, increase the fee, or renegotiate terms as your skills and the client's needs evolve.

How to Invoice Retainer Clients

One of the biggest advantages of retainers is that invoicing becomes almost boring. Same amount, same client, same date, every month. But there are a few nuances that, if you handle them well, will keep the arrangement running smoothly.

Invoice in advance, not arrears

This is the golden rule of retainer invoicing. Send the invoice at the start of the month (or a few days before), with payment due before work begins. This is standard practice — agencies do it, consultancies do it, SaaS companies do it. It protects your cash flow and creates clear expectations.

If a client pushes back on advance invoicing, hold firm. The retainer model only works if you're paid before you work — otherwise, you're just doing project work with a fixed monthly cap, and you've lost all the cash flow benefits.

Monthly invoicing structure

Your retainer invoice should be clean and simple:

Use a consistent invoice numbering system that includes the month — it makes both your records and the client's bookkeeping cleaner. Our free invoice generator handles this automatically.

Handling overages

When the client uses more than their retained hours, you need a clear process:

1. Notify at 80%. Send a brief email: "Hi [NAME], just a heads-up — we've used 16 of your 20 retained hours this month. Happy to continue working, but anything beyond 20 hours will be billed at £[OVERAGE RATE]/hour. Shall I proceed?"
2. Get written approval. Don't start overage work without a "yes" in writing. This protects you from disputes later.
3. Invoice overages separately. Send a separate overage invoice at the end of the month, clearly labelled and itemised by task. Don't lump it into next month's retainer invoice — keep it clean.

Dealing with unused hours

If your agreement is "use it or lose it," there's nothing to invoice — the client paid for your availability, and that's that. But if the client consistently uses only half their hours, it may be worth proactively suggesting a smaller retainer tier. This sounds counterintuitive, but it builds trust and makes the client far more likely to stick with you long-term.

A client who feels they're overpaying will eventually cancel. A client who feels you're looking out for them will stay for years.

Common Retainer Mistakes and How to Avoid Them

Retainers can transform your freelance income — but only if you avoid the mistakes that turn a predictable arrangement into an unprofitable headache. Here are the five that kill the most retainer deals.

Frequently Asked Questions

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Written by the team at Landolio — tools and templates for UK freelancers who'd rather do great work than chase payments.

This guide provides general information and is not legal advice. For complex contractual matters, consider consulting a solicitor.