Foundations · Lesson 1 of 4
How affiliate programmes work for publishers
About 10 minutes · Yogender Kumar, Managing Partner
By the end of this lesson you'll be able to
- Explain how a commission travels from a reader's click to your bank account
- Calculate earnings per click (EPC) for a programme
- Choose between programmes using EPC, approval rate and payment terms
Why this matters
Two programmes want their links in your most popular article. One pays 8% of each sale and the other pays £20 for each new customer. The bigger number isn't always the one that earns you more, and this lesson shows you how to tell.
The core idea
As a publisher (the site, channel or creator that sends the readers), you send readers to an advertiser through a tracking link. It carries your publisher ID, so the network knows the reader came from you.
If the reader buys within the cookie window, often 30 days, the sale is recorded against you. It starts as pending. The advertiser then checks it, which is called validation. Returned or cancelled orders are declined. The rest are approved, and the network pays approved commission in a regular payment run, usually monthly, once the advertiser has paid it and you pass a minimum payment threshold.
Programmes pay in a few ways:
- A percentage of each sale (CPS): common in retail.
- A fixed amount per action (CPA): a sign-up, a first order or a first paid month.
- A fixed amount per lead (CPL): an enquiry or a quote request.
- A fixed fee for a placement, sometimes called a tenancy: a set price for a spot on your site for a period, often on top of commission.
The number that lets you compare them is earnings per click (EPC): what you earn, on average, for each click you send. It combines three things:
EPC = conversion rate × commission per sale × approval rate
From your link to your bank account
One commission, start to finish
Worked example
Kettle & Crumb is an imaginary UK baking blog, so the figures here are illustrative. Its review of stand mixers sends about 1,000 clicks a month to whichever programme it links to.
Programme A is a kitchenware shop. It pays 8% on an average order of £150, which is £12 a sale. About 2% of clicks buy, and 90% of sales are approved after returns.
EPC is 0.02 × £12 × 0.9 = £0.216, about £0.22. On 1,000 clicks that's £216 a month.
Programme B is a recipe box company. It pays £20 for each new customer's first paid box. About 1.2% of clicks start a free trial, but only 70% of those go on to a paid first box.
EPC is 0.012 × £20 × 0.7 = £0.168, about £0.17. On 1,000 clicks that's £168 a month.
The £20 programme earns less, by about £48 a month on this article. Its £20 looks bigger than £12, but fewer readers act on it and more of those sales are taken back.
Payment terms matter too. Programme A pays monthly, once you pass £25. Programme B validates for 60 days before approving anything, so you wait longer for each payment.
My view: keep Programme A in the mixer review. Test Programme B in a recipe post, where readers are already thinking about dinner, and compare the EPC once it has a few dozen sign-ups behind it.
Earnings per click on Kettle & Crumb's mixer review
In practice
- Keep a simple sheet for each programme: rate, cookie window, validation period and payment threshold.
- Work out your own EPC once a link has at least 30 or so sales behind it. Before that, it's mostly chance.
- Check approval rates every month. A falling rate cuts your income even when sales look steady.
- Read the programme terms on traffic sources before you publish a link.
- Match each programme to the page where readers are closest to that decision.
Common mistakes
- Choosing by the headline rate. A higher commission can earn less per click. Compare EPC, not rates.
- Trusting the network's average EPC. It mixes every publisher's readers, and yours will behave differently. Measure your own.
- Forgetting the wait. A long validation period and a high payment threshold delay your money. Count them before you swap links.
Try it yourself
Programme C pays 5% on £80 orders. About 4% of your clicks buy, and 95% of sales are approved. Programme D pays £3 a lead. About 10% of your clicks become leads, and 60% are approved. What's the EPC on each, and which earns more per click?
Show answer
Programme C: 5% of £80 is £4 a sale. EPC = 0.04 × £4 × 0.95 = £0.152, about £0.15. Programme D: EPC = 0.10 × £3 × 0.6 = £0.18. Programme D earns about 3p more per click, if the approval rate holds.
Quick check
Not scored. Pick an answer to see the explanation.
What does EPC (earnings per click) tell you?
2% of your clicks buy, commission is £10 a sale and every sale is approved. What's your EPC?
Key takeaways
- A sale starts as pending, is checked by the advertiser, and is paid once approved.
- EPC is conversion rate × commission per sale × approval rate.
- A higher headline rate can earn less per click.
- Payment thresholds and validation periods decide when you're paid.