Attribution Window vs Refund Window, Explained | Harmonia

The short answer

An affiliate sale runs on two separate clocks, and keeping them straight is the most common thing brands get wrong.

• The attribution window decides whether a click still counts toward a sale. It measures time from the click to the purchase.
• The refund window decides whether an already-credited commission can reverse. It measures time from the purchase to a refund.

One clock credits the sale. The other can later claw it back. They start at different moments, measure different things, and you set each one per program. This guide walks through both, including how a refund reverses a commission in proportion to the amount returned.

The attribution window: does the click count?

The attribution window is how long after a click a purchase still counts for the athlete who drove it. You set it per program, in days.

A click does not have to turn into a sale the same minute. Someone taps an athlete's tracking link, thinks it over, and buys two days later. If two days falls inside your attribution window, the sale credits that athlete. If your window has already closed, the sale counts as organic and costs you nothing.

How it works in practice:

• Start: the clock starts at the click.
• Length: you choose the number of days when you launch the program.
• Result: a purchase inside the window credits the athlete; a purchase after it does not.

Because Harmonia uses first-party, server-side attribution, there is no discount code for the shopper to enter and no third-party cookie to expire. The ?ref= value rides inside your Shopify cart note attribute and is matched on our server, so the only thing that ends the credit is your attribution window closing, not the shopper's browser dropping a cookie.

See attribution windows for the product-side setting, and the attribution window glossary entry for the one-line definition.

The refund window: can a credited commission reverse?

The refund window is a separate period, measured from the purchase, during which a refund can reverse a commission that was already credited. It is tied to your return policy, not to how long a click stays valid.

The two clocks start at different moments:

• The attribution window starts at the click and ends before the purchase, deciding whether the sale credits at all.
• The refund window starts at the purchase and runs through your return period, deciding whether a credited commission gets reversed.

If an order is refunded inside the refund window, the commission reverses. If the refund lands after the refund window closes, the commission stands. This is why you set the two windows independently: a generous attribution window does not force a generous refund window, and the reverse is true too.

See refund handling for the setting, and the refund window glossary entry for the definition.

How a refund reverses a commission: proportional, pro-rated

A refund does not always wipe out the whole commission. The reversal is proportional to the amount refunded.

• Full refund: the full commission reverses.
• Partial refund: the same share of the commission reverses as the share of the order value returned.

Worked example, with a $10 per-sale commission on a $100 order:

$6athlete keeps after a 40% partial refund on a $10 commission

Cumulative-refund math for multiple refunds

A single order can be refunded more than once: a partial refund this week, another next week. Harmonia sums every refund on the order before working out the share, so the reversal tracks the cumulative amount returned, not each refund in isolation.

On the same $100 order with a $10 commission:

• A $30 refund returns 30% of the order, so $3 of commission reverses. The athlete keeps $7.
• A later $20 refund on the same order brings the total returned to $50, which is 50%. Total commission reversed is now $5, so a further $2 reverses. The athlete keeps $5.

Cumulative math means the second refund is measured against the whole order, not against what was left. The athlete is never reversed more than the share actually returned, and never reversed twice for the same dollars.

For the athlete-side view of what a reversal looks like and why it happens, see why a commission can reverse.

Why two clocks are more accurate, and fairer to athletes

Folding both timers into one number would force a bad trade. A long single window would leave commissions reversible for weeks after a sale is clearly final. A short single window would stop crediting real, slower purchases only to close the refund risk early. Splitting the clocks lets each one do its own job well.

• More accurate. The attribution window matches your buying cycle; the refund window matches your return policy. Two real-world clocks, set to two real-world numbers.
• Fairer to athletes. A reversal only ever takes back the share of a sale that was actually returned, and only inside the refund window. An athlete is not penalized for a return that lands after the window, and is never clawed back more than the customer sent back.
• Predictable for you. You know exactly when a credited sale becomes final: when its refund window closes. After that, the commission stands.

This fits how Harmonia treats athletes throughout. The click quality score is a sortable signal for brands, never an automatic clawback. Reversals come only from real refunds, measured proportionally.

Setting your two windows

Both windows are per-program settings you choose at launch and can adjust as you learn.

• Attribution window: match it to how long your shoppers take to decide. A 7-day window credits quick purchases; 30 days or more credits slower decisions and counts more sales toward athletes.
• Refund window: match it to your return policy. If you accept returns for 30 days, a 30-day refund window keeps commission reversibility aligned with the period a customer can actually send product back.

There is no single correct pair of numbers. Set them to your real cycle, watch how sales and reversals land, and adjust.

FAQ

What is the difference between an attribution window and a refund window?

They are two separate clocks. The attribution window decides whether a click still counts toward a sale: it measures the time from the click to the purchase. The refund window decides whether an already-credited commission can be reversed: it measures the time from the purchase to a refund. One clock credits the sale; the other can claw it back.

How long after a click does a sale still count?

For as long as your program's attribution window, which you set per program in days. If the purchase happens inside that window, the sale credits the athlete who drove the click. If it happens after the window closes, the sale counts as organic and costs you nothing.

How does a refund reverse a commission?

If an order is refunded inside your refund window, the commission reverses in proportion to the amount refunded. A full refund reverses the full commission. A partial refund reverses the same share of the commission as the share of the order value returned. The reversal uses cumulative-refund math, so multiple partial refunds on one order are summed before the share is calculated.

Is the whole commission clawed back on a partial refund?

No. A partial refund reverses only the matching share of the commission. If a shopper returns 40% of an order's value inside the refund window, 40% of the commission reverses and the athlete keeps the other 60%. Only a full refund reverses the full commission.

What attribution window should I set for my program?

Pick a window that matches how long your shoppers take to decide. A short window (for example 7 days) credits only quick purchases; a longer window (30 days or more) credits slower decisions but counts more sales toward athletes. Set it per program when you launch, and adjust it as you learn your buying cycle. The refund window is a separate setting tied to your return policy.