An affiliate link is a specially formatted URL that contains a unique identifier tying the link to a specific affiliate partner. When a user clicks the link and completes a qualifying action, such as making a purchase, the affiliate earns a commission. The tracking code embedded in the URL allows the merchant to attribute the sale to the correct affiliate.
Affiliate links typically include parameters like a partner ID, campaign identifier, and sometimes a sub-ID for granular tracking. These parameters make the URLs long and complex, so URL shortening can be used to create shorter versions for sharing on social media or by email. The short URL redirects to the full affiliate link, so all tracking parameters are carried over.
With a URL shortener's click analytics, you can see which channels bring the most clicks and at what times of day.
Some platforms' terms prohibit link cloaking, which hides where a link leads, and an affiliate link behind a short URL may violate their policies. In the United States, the FTC (Federal Trade Commission) guides in 16 CFR Part 255 (as of October 2026) give the example of a review blog that earns a share of sales through affiliate links, and say the reviews should clearly and conspicuously disclose that compensation. In Japan, according to the Consumer Affairs Agency, stealth marketing, which hides the fact that content is an advertisement, has violated the Act against Unjustifiable Premiums and Misleading Representations since October 1, 2023, and advertising includes content that a company asks or instructs a third party to post; the regulated party is the business that is the advertiser, and third parties such as influencers are not covered (as of October 2026).