Affiliate links are special URLs that track when someone clicks through and makes a purchase, so the person who shared the link earns a commission from the sale. You encounter them constantly: in product reviews, YouTube descriptions, blog recommendations, email newsletters, and social media posts. They look like normal links but contain a unique identifier that tells the retailer exactly who referred you.
How Affiliate Links Work
Every affiliate link contains a tracking ID that’s unique to the person sharing it. When you click one, a small piece of code called a cookie is stored on your device. That cookie connects your visit to the specific affiliate who sent you there. If you end up buying something, the retailer’s system reads the cookie, confirms which affiliate deserves credit, and logs a commission.
You’ll often notice affiliate links because they’re longer than a standard URL or contain strings of numbers and letters. A normal product link to a retailer might be clean and short, while an affiliate version of the same link includes extra parameters like “?ref=12345” or a completely different domain that redirects you. Some affiliates use link-shortening tools to make these URLs look tidier, but the tracking mechanism underneath works the same way.
The price you pay as a buyer doesn’t change. The commission comes out of the retailer’s marketing budget, not your wallet. Retailers prefer this model because they only pay when an actual sale happens, which makes it lower risk than traditional advertising.
Cookie Windows and When They Expire
The cookie placed on your device doesn’t last forever. Each affiliate program sets a “cookie duration,” which is the window of time during which a purchase still counts toward the affiliate’s commission. Most programs set this somewhere between 1 and 30 days, though some go much longer.
Short windows of around 7 days are common for products people buy on impulse or with little deliberation, like event tickets or inexpensive goods. A 30-day window is the most standard duration across the industry and works as a middle ground for products that involve some comparison shopping. Longer windows of 60 or 90 days show up with big-ticket items like software subscriptions or high-end electronics, where buyers tend to research for weeks before committing.
If you click an affiliate link, browse around, leave the site, and come back to buy within the cookie window, the affiliate still gets credit. If you come back after the cookie expires, or if you clear your browser cookies in the meantime, the affiliate earns nothing from your purchase.
Where You’ll Find Them
Affiliate links appear across nearly every content format online. Product review blogs are the classic example: a tech reviewer tests a laptop, writes about it, and links to the retailer’s product page using an affiliate URL. But they also show up in places you might not immediately expect.
- YouTube videos: Creators list affiliate links in video descriptions for gear, software, or products they mention.
- Social media posts: Instagram stories, TikTok bios, and X (Twitter) posts frequently contain affiliate links, sometimes through a “link in bio” page that aggregates multiple referral URLs.
- Email newsletters: Writers who recommend books, tools, or services often use affiliate links as a revenue stream alongside subscriptions or ads.
- Coupon and deal sites: Many of the “best deals” aggregators earn their revenue entirely through affiliate commissions on the products they list.
- Comparison articles: “Best credit cards” or “top mattresses” roundups are often structured around affiliate partnerships with the brands featured.
How Affiliates Get Paid
Commission structures vary widely depending on the product category and the retailer. Physical products typically pay affiliates a percentage of the sale price, often in the range of 1% to 10%. Digital products and software subscriptions tend to pay higher rates, sometimes 20% to 50%, because the retailer’s costs to deliver the product are lower.
Some programs pay a flat fee per sale rather than a percentage. Others use a “pay per lead” model, where the affiliate earns money when you sign up for a free trial or fill out a form, even if you never spend a dollar. The affiliate doesn’t set these rates. They’re determined by the retailer or the affiliate network that manages the program.
Large affiliate networks act as middlemen between retailers and the people promoting products. Platforms like CJ, ShareASale, impact.com, Awin, and ClickBank host thousands of affiliate programs in one place, handling the tracking, reporting, and payments. Some major retailers, like Amazon, run their own in-house affiliate programs instead of working through a network.
Disclosure Rules for Affiliate Links
The Federal Trade Commission requires anyone earning commissions through affiliate links to disclose that relationship clearly. The logic is straightforward: if someone is getting paid to recommend a product, you deserve to know that before deciding how much to trust the recommendation.
The FTC doesn’t require specific magic words, but the disclosure needs to be simple and hard to miss. Something like “I get commissions for purchases made through links in this post” is a good example. The phrase “paid link” placed right next to an affiliate URL is also considered adequate. Burying a disclosure on a separate page, hiding it behind a clickable “Disclosure” button, or dropping it in the comments section of a post does not meet the standard. The FTC has said those approaches are too easy for readers to skip.
The term “affiliate link” by itself may not be enough either. The FTC has noted that many consumers don’t understand the term means the person sharing the link earns money from purchases. A plain-language explanation works better. The disclosure should appear close to the recommendation it applies to, ideally visible at the same time the reader sees the link. A single disclosure buried on a homepage doesn’t cover individual posts or videos that a visitor might land on directly.
How Affiliate Links Affect What You Read
Affiliate links create a financial incentive for content creators to recommend products. That’s not inherently bad. Many reviewers and writers use affiliate income to fund the work of testing and evaluating products, and honest recommendations with affiliate links can genuinely help you find what you need.
But the incentive can also shape what gets recommended. A creator might feature a product with a generous affiliate commission over a competitor that pays nothing, even if the competitor is a better fit for most buyers. Roundup articles with titles like “10 Best” are particularly worth reading with a critical eye, since the selection of products and their ranking order can be influenced by which brands offer affiliate partnerships.
When you see affiliate links, the disclosure itself is actually useful information. It tells you the creator has a financial relationship with the brand, which you can factor into how much weight you give the recommendation. Trustworthy creators are transparent about this and still provide genuine evaluations. The red flag isn’t the presence of affiliate links. It’s the absence of any critical perspective alongside them.
What Happens on Your End
From your perspective as a buyer, clicking an affiliate link is functionally identical to clicking a regular link. You land on the same product page, see the same price, and go through the same checkout process. The retailer handles the commission on the back end. You’re not charged extra, and you don’t need to do anything differently.
The main thing that changes is the cookie stored on your device. If you’d prefer not to have affiliate tracking cookies, you can clear your browser cookies after visiting a site, use your browser’s private or incognito mode, or simply navigate to the retailer’s site directly instead of clicking through the affiliate link. None of these steps are necessary for your security; affiliate cookies don’t collect sensitive personal data. They simply log which affiliate sent you and when.