Refund Reserve Calculator

Size it on the peak, not the average.

Size it on the peak, not the average. Refunds arrive after the revenue has been spent, so the reserve has to be sized on the peak rather than the average.

Written and maintained by Mohit PatelLast checked August 4, 2026How we build these

Currency

Monthly revenue

Refund rate

Average days from sale to refund

Rolling reserve held by the processor

Reserve hold period

Peak month multiple of average

Reserve to hold

$55,736

$25,334 in a typical month

Refunds in flight, typical month$25,334

At peak$55,736

Processor rolling reserve$0

Total to hold$55,736

Refunds arrive after the revenue has been spent, which is why the reserve has to be sized on the peak rather than the average. January refunds against December revenue is where undercapitalised retailers fail.

How the Refund Reserve Calculator works

Refunds arrive after the revenue has been spent, so the reserve has to be sized on the peak rather than the average. January refunds against December revenue is where undercapitalised retailers fail.

Also known as: returns provision calculator · refund liability reserve · how much to hold for refunds

Why a reserve exists at all

Revenue recognised on a sale that will later be refunded was never really revenue. A refund reserve is the accounting acknowledgement of that: a liability set aside at the point of sale for the proportion you expect to give back.

Without one, profit is overstated in the month of sale and understated in the month of refund, and the pattern is worst exactly where it hurts most. A business with a strong November and December books excellent profit, then discovers in January that a fifth of it was never real.

The reserve smooths this. Recognise revenue net of expected refunds, hold the difference as a liability, and release it as refunds actually occur. The reported profit becomes a number you can plan from rather than one that gets revised downwards every January.

Sizing it from your own history

The reserve percentage should come from your own refund rate, measured over enough time to be stable, and adjusted for anything you know has changed. Twelve months of history is the usual basis; less than six is guesswork.

Seasonality has to be handled explicitly rather than averaged. If December sales refund at 30% and the rest of the year runs 18%, a flat annual rate under-reserves December and over-reserves the rest. Reserving by month against that month's expected rate is more work and materially more accurate.

Mix changes matter as much as seasonality. A business that added an apparel line to a homewares catalogue has a structurally higher refund rate going forward, and last year's percentage will under-reserve from the day the new range launches. The reserve rate should be reviewed whenever the catalogue changes shape, not annually out of habit.

Reserve as cash, not just as an entry

An accounting reserve prevents you overstating profit. It does not prevent you spending the money. Businesses that book a reserve correctly and then use the cash to buy inventory discover in January that the liability is real and the bank balance is not.

Holding the reserve as actual cash in a separate account is the version that protects you. It is unglamorous, it looks like idle capital, and it is the difference between a January refund wave being an inconvenience and being a crisis.

The amount to hold is the expected refunds on sales already made but still inside their return window. For a 30 day policy that is roughly one month of refunds; for 90 days it is three, which is a considerably larger number and one that catches sellers out when they extend a policy for marketing reasons without modelling the cash consequence.

What your payment processor holds

Processors run their own reserve against you and it works differently. A rolling reserve holds a percentage of each settlement for a fixed period, typically 5% to 10% for 90 to 180 days. It is theirs to hold, not yours, and it exists to cover chargebacks and refunds if you disappear.

The cash effect is significant and often underestimated. At £100,000 monthly volume with a 10% rolling reserve over 180 days, roughly £60,000 of your money is permanently held at steady state. It is not lost, and it is not available.

Reserves are negotiable, and the arguments that work are a stable refund rate, a low chargeback ratio, and trading history. Processors reduce or remove reserves for merchants who demonstrate both over time, and a surprising number of sellers never ask.

Keeping the reserve honest

The test of a reserve is whether releases match actual refunds. If you consistently release more than you use, you are over-reserving and understating profit. If you run out before the cohort's return window closes, you are under-reserving and the January revision is coming anyway.

Track it by cohort rather than in aggregate. Reserve set against October sales, refunds actually paid against October sales, and the variance. A few months of that shows whether the rate is right far more clearly than comparing total reserve to total refunds, which nets out errors in both directions.

Adjust the rate rather than the balance when it drifts. Topping up a reserve to cover a shortfall fixes this month and leaves the underlying rate wrong; changing the rate fixes every month after. The former is what most businesses do and it is why the reserve conversation recurs annually rather than being settled once.

Where to go next

The Refund Reserve question rarely arrives on its own. These are the ones that usually come with it:

Refund Impact on Profit Calculator — Ad spend is wasted on refunded orders too.
Working Capital Calculator — The quick ratio is the honest one.
Refund Rate Calculator — By value, so partial refunds count.
Etsy Fee Calculator — Every Etsy fee on one sale, itemised.

Not financial advice. Marketplace fees change, and they vary by country, plan and seller status. Every rate here is an editable default, not a quoted price, check the platform's current fee schedule before you price a product against it. This is not tax or business advice.

Frequently asked questions

How large should a refund reserve be?

Enough to cover refunds in flight at peak, plus any rolling reserve the processor holds. Sizing it on the average month leaves you short exactly when the pressure is highest.

What is a processor rolling reserve?

A percentage of your revenue the payment processor withholds against future refunds and chargebacks, released after a period. It is common for newer or higher-risk merchants.

Why does seasonality matter so much?

Because refunds lag sales by weeks. A December peak generates January refunds against January's lower revenue, and the gap has to be funded from cash you may already have committed.

Should the reserve be a separate account?

Practically, yes. Money in the main account gets spent, and the discipline of a separate balance is what makes the reserve exist when it is needed.

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