Affiliate cookie windows explained: what the number really means

A cookie window is the number of days after a click during which a purchase still earns you a commission. "30-day cookie" means a reader who clicks your link today and buys in three weeks still counts. Buy on day 31 and the sale is nobody's.

That much is on every program page. What the number does not tell you is when it stops mattering, and that depends on three things it leaves out: what resets it, who else is in the race, and how long your readers actually take to decide.

When the clock starts and what resets it

The clock starts at the click, not at the visit or the sign-up. Most programs set the cookie the moment the reader lands through your link.

A new click on your link by the same reader normally starts a fresh window. A click on someone else's link usually replaces yours, because most programs attribute on last click. The window is not "you get credit for 30 days". It is "you get credit for 30 days unless another affiliate is clicked after you".

Some programs attribute on first click instead, and a few split credit. Programs rarely advertise which one they use. It is in the terms, usually near the cookie clause.

Why last click matters more than the length

Under last click, the length of your window only protects you from time, never from competition. A reader who reads your comparison, clicks through, leaves, then searches for a discount code and clicks a coupon site's link before checking out credits the coupon site, whatever your window says.

That is why the same 30-day window is worth a lot to a site that sends readers who buy on the spot, and much less to a site that sends readers early in their research. If your content is the first thing people read, look for programs that attribute on first click or that exclude coupon sites, rather than chasing longer windows.

Cookie window, refund window and approval period are different things

Three time periods sit on most program pages, and they are easy to mix up:

• Cookie window: how long after the click a purchase counts.
• Refund or return window: how long the customer can get their money back. A refund reverses your commission.
• Approval or locking period: how long the program holds a commission as pending before approving it, usually long enough for the refund window to pass.

A program can have a long cookie window and still pay slowly because the approval period is long. That part lives in the payout terms.

What shortens a cookie window in practice

The stated window is a maximum. Several things cut it short:

• Browser tracking protection. Safari and Firefox limit or block the cookies affiliate tracking traditionally relies on, and can shorten how long a cookie lives. The stated window may not survive on those browsers.
• Ad blockers and private browsing. Some block the tracking redirect entirely, so no cookie is set.
• Device switching. A click on a phone and a purchase on a laptop are two different browsers.
• Cleared cookies. Rare, but it happens.

Programs that use server-to-server tracking, sometimes called postback tracking, record the click on their own servers and are much less exposed to all four. If a program mentions it, that is worth more than a few extra days on the window.

How long should a cookie window be?

Long enough to cover the time your readers take to decide. Beyond that, extra days add little. A rough way to think about it:

• Impulse and low-price purchases (a book, a cheap accessory, a one-off digital product): most buyers decide within a day or two. A 7-day window covers almost all of it.
• Considered consumer purchases (a mattress, a course, a holiday): buyers compare and come back. Two to four weeks is where the window starts to matter.
• Business software and services: a trial, a team discussion, a budget sign-off. The decision can take a month or more, so a short window can quietly miss most of the sales you started. Subscription software adds another wrinkle, because the commission often recurs, and our list of the highest paying SaaS affiliate programs covers how trials and renewals change what those programs pay.

Compare the window to the product's buying cycle, not to other programs' windows. A 90-day window on a product people buy on the spot is a nice number with no effect, and a 7-day window on software with a six-week trial will miss most of the conversions you set up.

Does a longer cookie window always pay more?

No. A window only matters for purchases that happen after the click and before it expires, and only if no other affiliate gets a later click. For impulse purchases most sales happen within a day, so a longer window adds little. It matters most for considered purchases with long buying cycles.

Does clicking my own link again reset the cookie window?

Usually a new click from the same reader starts a fresh window, but clicking your own link to make your own purchase is a self-referral, which most programs forbid and reverse.

Checking the window before you join

Look for the cookie clause on the program's own terms page and note three things: the length, first or last click, and whether coupon or cashback sites can override you. Every program listing in this directory shows the cookie window we read from the company's own page, with a link to that page, so you can check the wording yourself. For how the window fits with the rest of the terms, start from how affiliate programs work, and compare it against the commission type before deciding.