That’s Not a Retainer, It’s a Payment Schedule
Most design firms do not sell retainers. They take a deposit against a flat fee, collect the rest as the work moves through phases, and call the whole arrangement a retainer. Those are two different things. A retainer buys ongoing availability for a recurring fee. A deposit is money paid in advance against work that has already been scoped and priced.
The distinction is not pedantry. Using the wrong word creates three specific problems: the client hears a promise the firm did not make, the money arrives on a schedule that has nothing to do with when costs land, and the term itself carries an implication about whose money it is.
What a retainer actually is
A retainer is a recurring fee paid in exchange for a defined, continuing claim on a firm's time, whether or not that time is used in a given period.
The load-bearing part of that definition is the last clause. A client on a genuine retainer is buying access. If they go quiet for a month, the fee is still earned, because what they purchased was the guarantee of availability rather than a deliverable.
Retainers do exist in design. They fit a long-running commercial relationship, a repeat developer client, or an ongoing advisory arrangement where a firm needs to hold capacity open. They are not how most design work is paid for, and most firms that believe they have one do not.
What most design firms actually have
The common arrangement is a flat fee for a scoped project, part of it collected up front, the remainder released as the work moves through design phases.
That is a payment schedule against a deposit, and every mechanic in it differs from a retainer. The total is fixed in advance, because the scope was priced before the agreement was signed. Payments are triggered by progress rather than by the calendar. If the client goes quiet, no further fee is earned, because nothing further was delivered. When the scope is complete, the arrangement ends — there is nothing recurring about it.
None of that is a criticism of the structure. It is the correct structure for scoped project work. The problem is only the label attached to it.
What the client is buying
True retainer: Access and reserved capacity
Deposit + payment schedule: A defined, priced scope
What triggers payment
True retainer: The calendar — the same date each period
Deposit + payment schedule: Progress — a phase completes or a milestone is met
First payment
True retainer: The first period's fee
Deposit + payment schedule: An initial payment, sized to the fee structure
Is the total known at signing?
True retainer: No — it accrues as long as the arrangement runs
Deposit + payment schedule: Yes — it was priced before the agreement
If the client goes quiet
True retainer: Fee is still earned
Deposit + payment schedule: Nothing further is earned; work and billing both stop
How it ends
True retainer: On notice from either side
Deposit + payment schedule: When the scope is complete
Money left at the end
True retainer: Earned. Nothing to return
Deposit + payment schedule: Applied to the final invoice, or returned, per the agreement
That first payment is a deposit against a known total, not a retainer, because the total was set before anyone signed. What that total should be in the first place is a separate question, covered in What Interior Design Firms Actually Charge.
How big should the first payment be?
There is no single correct percentage, because the right number depends on the fee structure underneath it. A flat fee split across design phases, an hourly engagement opened with a starting balance, and a cost-plus arrangement each imply a different amount at signing. A firm that copies a percentage from someone working in a different structure will get it wrong.
Published guidance reflects that spread rather than resolving it. Design-business sources including Studio Designer and TALD describe flat-fee work being split into milestone payments tied to deliverables — some firms at 50/25/25 across kickoff, design presentation and final approval, others in equal thirds — while a common alternative frames the first payment as a discovery and onboarding milestone of 20–25% of the total, due at contract signing. Those are different structures producing different first payments, not competing answers to the same question.
So the useful test is not a percentage at all. The first payment should cover the work between signing and the next payment trigger, plus the firm's fixed costs across that stretch. Work backwards from that and the percentage falls out of your own numbers, which is the only place it can legitimately come from.
Problem one: the client hears a promise you did not make
A client who believes they are "on retainer" believes they have bought availability. That is what the word means everywhere else they have encountered it.
So they call between phases. They expect same-day answers. They treat questions outside the scoped work as already covered, because in their understanding of the arrangement, they are paying for the firm to be there.
The firm did not agree to any of that and usually did not charge for it. But the expectation came from the agreement's own vocabulary, which makes it hard to push back on without appearing to withdraw something. It is also the cheapest of the three problems to fix: a wording change, made once.
Problem two: phase-triggered money does not line up with monthly costs
Payroll is monthly. Rent is monthly. Software, insurance, and the draw the owner takes are monthly.
Design phases are none of those things. A phase ends when the work and the client's decisions say it ends, and that is not a date the firm controls. A client who takes time over a selection, a consultant who is late, an approval waiting on someone else — each moves the trigger for the next payment without moving any of the costs the firm is carrying meanwhile.
This is the mechanical reason a firm can be fully booked, profitable on the project, and still short of cash in a given month. The margin is real. The money is simply not scheduled to arrive when the obligations are.
Calling the arrangement a retainer hides this, because the word implies a monthly rhythm the agreement does not actually contain. Naming it a payment schedule makes the gaps visible, which is the first step to structuring around them.
Problem three: "retainer" carries an implication about whose money it is
In other professional contexts — law most prominently — a retainer can mean funds held on account for the client's benefit until earned, sometimes under rules about how those funds must be held.
Design firms are not generally subject to those rules, and a deposit against a priced scope is a different instrument. But the word travels with the connotation, and a client who has met "retainer" elsewhere may reasonably believe the money is theirs until drawn against, and refundable on request.
Whether that belief is correct depends on the agreement and on where the firm practices. It is worth having an attorney look at the payment language for that reason alone. The safer habit is to avoid inheriting an argument that better wording would have prevented.
What to call each payment instead
Name each payment for the thing that triggers it, and say in the agreement what it is applied to.
At signing
Call it: Initial payment or deposit, applied to the final invoice
What it must be sized to cover: The work between signing and the next trigger, plus the firm's fixed costs across that stretch
At each phase transition
Call it: Phase payment, named for the phase it releases
What it must be sized to cover: The phase it precedes, not the one just finished
Anything outside scope
Call it: Additional services, priced separately
What it must be sized to cover: Itself
Ongoing access after completion
Call it: A retainer, if that is genuinely what it is
What it must be sized to cover: Reserved capacity, used or not
The last column carries the rule worth stating on its own: each payment should land before the phase it funds, not after. A schedule that bills on completion asks the firm to finance its client, one phase at a time.
Where those terms live, and what else belongs alongside them, is covered in What Belongs in an Interior Design Letter Agreement. How the total itself gets set — and whether a flat fee is the right container in the first place — is in Flat Fee vs. Hourly vs. Cost-Plus: Which Actually Makes You Money.
If you do want a real retainer
Some relationships genuinely warrant one. Two terms decide whether it works. The first is a cap — sell a stated number of hours or a stated number of requests per period, never "ongoing support." Unbounded language gets read generously, and a client with an uncapped arrangement usually believes they are using it correctly. The second is what happens to unused capacity: say explicitly whether hours roll over. Rollover turns a retainer into an accumulating obligation the firm is no longer being paid against.
A retainer also has a prerequisite that has nothing to do with the document. It is a promise of availability, so a firm whose project work already consumes every hour will break it. Sell one only against capacity that actually exists.
The change is smaller than it sounds
Nothing here requires repricing the work or renegotiating with a current client. Change the label, tie each payment to a named trigger, and state what each one is applied to. The fee stays the same.
What changes is that the client's expectations now match the arrangement they actually signed, and the firm can see where its own cash gaps sit — the part that was invisible while the whole thing was called a retainer.
Frequently asked questions
What is the difference between a retainer and a deposit in interior design? A retainer is a recurring fee that buys continuing access to a firm's time, earned whether or not the client uses it. A deposit is an advance payment against a project that has already been scoped and priced, applied to the total. Most design agreements described as retainers are deposits.
How much should a design firm take up front? There is no single percentage, because it depends on the fee structure. Published guidance ranges from a discovery and onboarding milestone of 20–25% at signing to a flat fee split 50/25/25 or in equal thirds. The test that matters is whether the payment covers the work and the fixed costs between signing and the next payment trigger.
Should design payments be tied to dates or to phases? To phases or named deliverables. Date-based payments imply a retainer and create the expectation of ongoing availability. Phase-based payments should be scheduled to land before the phase they fund rather than after it.
Is a design deposit refundable? That depends on the agreement and on local rules, which is a reason to have an attorney review the payment language. The word "retainer" is often read as implying the money is held for the client until earned, so an agreement that means "deposit" should say deposit.
When does a design firm actually need a retainer? When a client is genuinely buying reserved capacity rather than a scoped project — a long-running commercial relationship, a repeat developer, or ongoing advisory work. It requires a usage cap, a stated rule on unused hours, and real capacity to honour it.
19th & Co advises founder-led architecture and interior design firms on fees, hiring, operations, and business development. Founded by Christine Woodward — M.Arch, MBA candidate at Johns Hopkins, and graduate studies in management at Harvard, with fifteen years in practice — the firm has worked inside more than 500 design firms, delivered over 5,000 advising hours, and worked alongside more than 1,000 designers and firm leaders.
If you want your payment terms read through before a client sees them, you can book a call on my calendar here.
Last updated: September 2026
