Retainer
Agency glossary · Updated July 2026
Definition
A retainer is an ongoing agreement where a client pays an agency a fixed recurring fee, usually monthly, for an agreed scope of work or a set amount of capacity. It gives the agency predictable revenue and the client priority access, instead of billing project by project.
Why it matters
Retainers turn unpredictable project income into recurring revenue you can count on before the month starts, which funds payroll and lets you plan and hire ahead of demand.
Two common models
A scope-based retainer covers a defined set of deliverables each month; a capacity or hours-based retainer reserves a set number of hours. Either way, define what happens when the client goes over the agreed scope.
The three things "retainer" can mean
The word covers three arrangements that behave very differently, and a contract that does not say which one it means is a contract waiting for an argument.
A retainer for availability. The client pays to have first call on your time, whether or not they use it. Unused time does not roll over, because what was bought was the availability rather than the hours.
A retainer for a fixed scope. A monthly fee for a defined amount of work: so many deliverables, so many hours, so many campaigns. This is what almost every agency means by the word, and it is the one that needs a stated overage price.
A retainer held on account. The client deposits money that is drawn down as work is done, with the balance returned if unused. This is the sense a law firm means, and it is closer to a deposit than to a subscription.
The first two are revenue when invoiced. The third is not yours until the work is done against it, which is an accounting difference as much as a commercial one.
What a retainer means in business terms
For the client, a retainer converts an unpredictable cost into a budgeted line and guarantees access to people who would otherwise be booked. For the agency it converts project work, which stops, into recurring revenue, which does not, and that is what makes staffing possible: you cannot hire against work you might win.
The trade is real on both sides. The client gives up the flexibility to spend nothing in a quiet month. The agency gives up the upside of a big one-off project and takes on the obligation to be available. Retainers that fail usually failed because one side thought they had bought something the other side had not sold.
See it in AgencyKit
Frequently asked questions
A retainer is an ongoing agreement where a client pays a fixed recurring fee, usually monthly, for an agreed scope or amount of capacity. It gives the agency predictable recurring revenue and the client priority access, instead of one-off project billing.
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