What it means
The mechanics are straightforward. An affiliate receives a unique tracking link, a customer clicks it, a cookie or server-side identifier records the referral, and if a purchase follows within the agreed window the affiliate earns commission.
Payment is triggered by performance rather than by exposure, which distinguishes it from buying advertising space. Affiliates come in several types: content publishers and review sites, coupon and cashback sites, email list owners, comparison engines, and individual creators with an audience.
Each type behaves differently, and a programme dominated by coupon sites often looks profitable while quietly paying commission on customers who were going to buy anyway. Commission structures vary.
Common models include a percentage of order value, a flat fee per sale, a fee per qualified lead, and tiered rates that increase once an affiliate passes a volume threshold. Recurring commissions on subscription revenue are common in software, though most programmes cap them at 12 or 24 months.
The financial appeal is that the cost is variable and known in advance, so it scales with revenue rather than sitting as a fixed commitment. The corresponding risks are attribution disputes, brand safety where partners make claims the business cannot support, and fraud through fake leads or hijacked traffic.
Good programmes are managed rather than left to run. That means clear terms on which sales qualify, a cooling-off period before payout, regular checks on where traffic comes from, and periodic tests to confirm that affiliate-sourced customers really are incremental rather than customers who would have arrived anyway.
In practice
Real-world examples
Example 1
A subscription vitamin brand pays creators $25 for every first order placed through their link, with a 60-day hold before payment to allow for cancellations and refunds.
Example 2
A travel booking site runs a comparison affiliate programme paying 4% of the booking value, and finds that a single review publisher accounts for 38% of all affiliate revenue, prompting a negotiated exclusive rate.
Example 3
A business software company offers affiliates 20% of subscription revenue for the first 12 months, then reviews the programme after discovering that several partners were bidding on its own brand name in paid search.
Think of it
Imagine running a bookshop and letting local café owners keep ten percent of the cover price for every customer they send your way who buys a book. You only pay them when cash actually enters the till.
Formula
Calculation
Affiliate commission = number of qualifying sales x average order value x commission rate
Number of qualifying sales = clicks x conversion rate
An online outdoor gear retailer runs a programme paying 12% of order value. In one month, its affiliates send 10,000 clicks, which convert at 3%, and the average order value is $80.
Qualifying sales = 10,000 x 3% = 300 sales
Affiliate-generated revenue = 300 x $80 = $24,000
Commission payable = $24,000 x 12% = $2,880
Effective cost per sale = $2,880 / 300 = $9.60
Revenue retained after commission = $24,000 - $2,880 = $21,120
If the retailer's gross margin before commission is 45%, gross profit on that revenue is $10,800, so the $2,880 commission leaves $7,920 of contribution. The programme is worthwhile as long as those sales are genuinely additional, which is the test that matters far more than the commission rate itself.Case study
Seen in the real world
This is an illustrative, fictional example. Brightwater Kitchenware, an invented cookware brand, launched an affiliate programme paying 15% of order value and grew affiliate revenue to $1,800,000 in its first year, at a commission cost of $270,000. On the surface the channel looked like the cheapest source of growth in the business.
A closer review told a different story. Roughly 55% of affiliate revenue came from three cashback and voucher sites, and a holdout test showed that most of those customers had already reached the checkout page before clicking through to claim a discount code. The brand was paying commission and giving a discount on sales it had already won.
Brightwater restructured the programme: voucher sites moved to a 4% rate with a last-click exclusion when the visitor had already been on the site that session, while content publishers moved to 18%. Affiliate revenue fell to $1,450,000 the following year, but commission dropped to $155,000 and contribution from the channel rose, which the team treated as the honest measure of success.
Watch out
Common mistakes
- Judging an affiliate programme on total revenue attributed to it. Much of that revenue can be sales the business would have made anyway, so incremental testing matters more than the attribution report.
- Paying commission immediately on order. Without a hold period covering returns and cancellations, a business ends up paying for revenue it never keeps.
- Leaving the terms silent on brand bidding and discount codes. Partners will otherwise compete against the brand's own paid search and issue codes that erode margin.
Questions
People also ask
Is affiliate marketing the same as influencer marketing?
Not quite, since influencers are often paid a flat fee for content regardless of results, while affiliates are paid only when a tracked action occurs, though the two models increasingly overlap.
How is affiliate commission treated in the accounts?
It is normally a selling expense recognised when the qualifying sale occurs, with an accrual for commission earned but not yet paid at the period end.
What commission rate is normal?
Rates commonly run from around 3% on low-margin retail goods to 30% or more on digital products, and the sensible ceiling is set by gross margin rather than by what competitors advertise.