Affiliate Marketing Terms Explained: Commission, CPA, EPC, Cookie Windows and More

Affiliate marketing has its own vocabulary, and most of it comes down to one idea: a creator shares a tracked link or code, a shopper buys, and the brand pays the creator a commission for that sale. Commission, CPA, EPC, cookie windows and attribution are simply the words for how that sale is counted and how much it pays. This guide explains each term in plain English, with a worked example, so you can read any affiliate program's terms and know exactly what you are signing up for.

Whether you are a creator choosing which Black-owned brands to promote or a brand setting up your first program, these are the terms you will meet first.

What Is Affiliate Marketing?

Affiliate marketing is performance-based promotion. A business gives a promoter, called an affiliate, a unique link or discount code. When someone buys through that link or code, the sale is credited to the affiliate and the business pays them an agreed reward, usually a percentage of the sale. The UK's Advertising Standards Authority describes it the same way: an affiliate is rewarded by a business for each new customer attracted by their marketing efforts, usually with a pre-agreed percentage of each sale.

The key word is performance. The brand pays for results rather than for posts or impressions, which is why affiliate programs suit small businesses watching every dollar and creators who want income that grows with their audience.

What Is an Affiliate Link?

An affiliate link is a normal web address with tracking added. When a shopper clicks it, the affiliate platform records the click and remembers which affiliate sent that shopper, then forwards them to the brand's store. If they buy, the sale is matched back to the click.

Some programs also issue an affiliate code, a discount code tied to one affiliate. Codes are useful anywhere a link is awkward, such as a podcast, a video voiceover or a conversation at a market stall.

What Is a Commission?

A commission is what the affiliate earns for a sale. It is usually set as one of two things:

• A percentage of the sale, for example 10% of the order value.
• A flat fee per sale, for example a fixed amount for each new customer.

Read the small print on what the percentage is calculated from. Many programs pay on the order subtotal, which usually leaves out shipping and taxes, and most reverse the commission if the order is refunded or canceled.

What Does CPA Mean?

CPA stands for cost per acquisition (sometimes cost per action). It is the amount a brand pays for one result, usually one sale. From the brand's side, CPA is a cost. From the affiliate's side, the same number is the commission they earn per sale. A flat-fee program is a fixed CPA; a percentage program has a CPA that changes with each order's value.

CPA is why affiliate marketing is attractive to growing brands: the brand knows its cost per sale in advance and only pays it when a sale actually happens.

What Is a Conversion?

A conversion is the action a program pays for. In most programs it is a completed purchase, but it can also be a sign-up, a booking or a first order from a new customer. The conversion rate is the share of clicks that turn into conversions. If 200 people click your link and 4 of them buy, your conversion rate is 2%.

What Is a Cookie Window?

A cookie window, also called the cookie duration or attribution window, is how long after a click a sale still counts for the affiliate. With a 30-day window, a shopper who clicks your link today and buys within the next 30 days is credited to you, even if they leave and come back later. After the window closes, a new purchase is no longer credited to that click.

Longer windows favor products people think about before buying, such as furniture or skincare routines. Shorter windows are common for everyday purchases. When you compare programs, compare the window as well as the commission rate.

What Is Attribution?

Attribution is the set of rules that decides which affiliate gets credit for a sale. The most common rule is last click: if a shopper clicked two different affiliates' links before buying, the most recent click inside the cookie window gets the commission. Codes add a second route: if a shopper types an affiliate's code at checkout, the sale can be credited to that code even with no click. Each program states its own rules, so check how it handles a click and a code on the same order.

What Does EPC Mean?

EPC stands for earnings per click. It is the average amount an affiliate earns for every click they send, and it is the single most useful number for comparing programs, because it combines the commission rate, the average order value and the conversion rate into one figure.

The formula is simple: total commission earned divided by total clicks. Many networks show EPC per 100 clicks to make the numbers easier to read.

How Do These Numbers Fit Together?

Here is a worked example with round numbers, for illustration only:

• You send 500 clicks to a brand.
• 10 of those shoppers buy, so your conversion rate is 2%.
• The average order is $60, and the program pays 10% commission, so you earn $6 per sale.
• Total earnings: 10 sales times $6 = $60.
• EPC: $60 divided by 500 clicks = $0.12 per click, or $12 per 100 clicks.

Now compare a second brand paying 20% commission but converting only 0.5% of clicks. Same 500 clicks, 2.5 sales on average, $12 per sale, about $30 in total, an EPC of $0.06. The higher commission rate pays half as much. That is why experienced affiliates look at EPC, not just the headline rate.

What Is an Affiliate Network?

An affiliate network is the platform that sits between brands and affiliates. It provides the tracking links and codes, records clicks and sales, applies the attribution rules, calculates commissions and handles payouts. Without a network, a brand would have to build all of that tracking itself.

Afrofiliate is an affiliate network built for Black-owned businesses: brands run performance-based affiliate programs, and creators, publishers and communities earn commission for every sale they send.

What Is a Publisher?

Publisher is the industry's umbrella word for anyone who promotes a brand for commission: creators, bloggers, newsletter writers, podcasters, coupon sites, comparison sites and community groups. On most networks, "publisher" and "affiliate" mean the same thing. The brand on the other side is called the advertiser or merchant.

What Is a Payout Threshold?

A payout threshold is the minimum balance you need before a network or program pays you. Commissions also usually sit in a pending state for a while before they become payable, so that refunds and returns can be taken back out first. Check both the threshold and the pending period, because together they decide how soon you are actually paid.

Do I Have to Tell My Audience About Affiliate Links?

Yes. In the US, the FTC's rules on endorsements, published as 16 CFR Part 255, require a clear disclosure when you have a material connection to a brand you promote, and earning a commission is one. In the UK, the ASA's guidance says affiliate marketing must be obviously identifiable as advertising, and that both the brand and the affiliate are responsible. A short, clear label near the link, such as "ad" or "affiliate link", is the safe habit on every platform.

Where Should I Start?

If you are a creator, start with brands you already buy from and talk about, look at each program's commission, cookie window and payout terms, and track your EPC once clicks start coming in. If you are a Black-owned brand, decide what a new customer is worth to you, set a commission you can sustain at that CPA, and give affiliates the links, codes and product images they need to promote you well.

Both sides start in the same place: sign up at Afrofiliate, browse or create programs and start earning from the sales you send.