Affiliate link
A unique URL given to an affiliate that tracks clicks and conversions back to them through a tracking parameter or subdomain. When a visitor clicks the link, a cookie drops in their browser identifying the affiliate. If the visitor purchases within the cookie window, the affiliate is credited with the commission. The affiliate link is the technical backbone of every affiliate program; without it, attribution falls apart and nobody gets paid for what they sold.
Why the link is the program
Strip everything else away and an affiliate program is fundamentally a link with rules attached. Three reasons that link does so much work.
Attribution depends on it
The entire commission structure hangs on knowing which affiliate produced which sale. Lose the link tracking and the whole program collapses overnight; nobody gets paid because nobody can prove what they sold.
Each affiliate has skin in the game
A unique link per affiliate is a small contract that says this person is responsible for this traffic. Without per-affiliate links, you can only know "an affiliate referred this sale," which makes paying the right person impossible.
Sub-tracking unlocks insights
Affiliates who add sub-IDs (a YouTube version, a Twitter version, an email version of the same link) get back data showing which channel actually converts. That makes affiliate marketing tractable instead of a guessing game.
How affiliate link tracking works
Five things happen between the click and the commission. Each one has a way of failing if not built carefully.
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Generated on signup
When an affiliate joins the program, the platform creates a unique tracking ID and a link that contains it (something like systeme.io/?sa=sa00123abc). The ID is permanent; the affiliate will use the same link for the life of the program.
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Click drops a tracking cookie
Visitor clicks the link, the destination server reads the tracking ID from the URL, and a first-party cookie drops in the visitor's browser with that ID. From that moment on, the visitor is "tagged" as belonging to that affiliate's referral.
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Cookie persists for the window
The cookie has an expiry equal to the cookie window (default 60 days on most platforms). During that window, every subsequent visit from that browser is still tagged to the affiliate, even if the visitor comes back via a different channel.
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Purchase fires a conversion event
When the visitor checks out, the checkout reads the cookie and writes the affiliate's ID into the order record. The commission is calculated automatically based on the configured rate. The sale shows up in the affiliate's dashboard within minutes.
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Commission credited to the affiliate
Once the order clears any refund window, the commission moves from "pending" to "approved" in the affiliate's balance. On the next scheduled payout date, the platform sends the balance to the affiliate's PayPal address automatically.
What affiliate links look like in practice
Three real-world link patterns affiliates actually use across different channels.
Raw tracking link
The standard format: systeme.io/?sa=sa00123abc. Functional, ugly, and obviously a tracking link. Click rate on a bare link in a YouTube description averages 60% of what a cloaked version achieves, because viewers recognise the affiliate tag.
Branded redirect link
The affiliate's own domain redirects through to the tracking URL: brand.com/go/systeme. Looks like a regular link, increases click-through rate by 15% to 25%, and protects the affiliate's tracking ID from being copied or swapped.
Campaign-tagged link
The same affiliate link with an extra sub-ID parameter per channel: systeme.io/?sa=sa00123abc&sub=youtube-aug. The affiliate now sees clicks and conversions broken out by source, so they can double down on what works and cut what doesn't.
What to watch on every affiliate link
Eight numbers per affiliate or per link. The first few are obvious; the last few catch the silent failures most programs miss.
Total clicks
Raw click volume on the link. The denominator for every other rate-based metric.
Cookie set rate
Percentage of clicks that successfully set a tracking cookie. Below 80% means a browser-blocking issue (incognito, third-party cookies disabled).
Conversion rate per link
Sales divided by clicks. Compares the quality of traffic each affiliate sends; high-converting affiliates deserve higher commission tiers.
Revenue per click
Total revenue divided by clicks. The cleanest measure of link economic value.
Sub-ID breakdown
Performance by sub-ID (YouTube, Twitter, email). Tells the affiliate which channels actually produce, so they can focus effort.
Cross-device drop-off
Estimated share of conversions lost because the buyer switched devices between click and purchase. Sized via incognito-versus-tracked benchmarks.
Cookie window expiry
Time to conversion distribution. If most sales happen in days 1 to 7, a 60-day cookie is overkill; if some happen at day 50, shortening would lose revenue.
Self-referral attempts
Cases where an affiliate tried to buy through their own link. Most platforms block these automatically; high attempts suggest the commission rate may need adjustment.
Related glossary terms
Concepts that sit alongside the affiliate link. Read each one before designing the tracking and attribution rules.
How systeme.io handles affiliate links
Auto-generated unique links, sub-ID support, cookie-based tracking, and anti-self-referral protection all ship with the built-in affiliate program. Included on the free plan.
Auto-generated unique link per affiliate
The moment an affiliate joins, a unique tracking link is generated and shown in their dashboard. No manual setup, no editing required.
First-party cookie tracking
Cookies drop on the systeme.io domain, persist for the configured window, and survive the third-party cookie restrictions most browsers now enforce.
Per-campaign sub-IDs
Affiliates append a sub-ID to track different channels with the same root link. Conversion data breaks out per sub-ID inside the affiliate dashboard.
Custom domain link cloaking
Optional support for branded redirects on the affiliate's own domain. Lift click-through rate without losing tracking.
Anti-self-referral protection
Detects when an affiliate tries to buy through their own link and blocks the commission automatically. Prevents the most common form of program abuse.
Click and conversion analytics
Clicks, conversion rate, revenue per click, and sub-ID performance all visible in the affiliate dashboard and the merchant view.
Frequently asked questions
Common questions about affiliate links, and how each one plays out inside systeme.io.
An affiliate link is a unique URL given to an affiliate that tracks clicks and conversions back to them. Each affiliate gets a different link with their tracking ID embedded (something like systeme.io/?sa=sa00123abc). When a visitor clicks the link, a cookie drops in their browser identifying the affiliate. If that visitor purchases within the cookie window, the affiliate is credited with the commission. Without affiliate links, there is no way to attribute sales to specific affiliates, and the whole program falls apart.
Three things happen in sequence. One: the visitor clicks the affiliate link, which contains the affiliate's unique tracking ID as a URL parameter. Two: the destination server reads the ID and drops a first-party cookie in the visitor's browser, recording that affiliate as the referrer. Three: if the visitor buys within the cookie window (usually 30 to 90 days), the checkout reads the cookie and credits the sale to that affiliate. The cookie is the link between the click moment and the eventual purchase.
Cloaked affiliate links replace the raw tracking URL with a branded version (brand.com/go/topic instead of systeme.io/?sa=sa00123abc). Cloaking exists for three reasons: cleaner appearance in social posts and email, click-through rates that lift by 10% to 20% on shorter links, and protection against affiliate ID theft (a raw link can be copied and the ID swapped). Most platforms support cloaking either natively or through a redirect on the affiliate's own domain.
Most platforms let affiliates add a sub-ID or campaign parameter to track which content or channel produced the click. The same affiliate can use one link variant on YouTube, another on Twitter, another in a newsletter, and see clicks and conversions broken out by source. Some platforms also let affiliates redirect their tracking link to a specific landing page on the merchant's site (deep-linking) so promotions can target product pages directly instead of the homepage.
As long as the purchase happens within the cookie window (most programs use 30 to 90 days), the affiliate is still credited. The cookie sits in the visitor's browser; when they return to the site and check out, the checkout reads the cookie and attributes the sale. Limitations: the visitor must use the same browser and device, and they must not clear cookies between click and purchase. Cross-device purchases and incognito browsing usually break attribution.
systeme.io generates a unique affiliate link the moment a partner joins the program. The link drops a first-party cookie that persists for the configured window (default 60 days). Affiliates can add sub-IDs to track different channels, view click and conversion data per sub-ID, and see real-time stats in their dashboard. Anti-self-referral protection blocks affiliates from earning on their own purchases. Optional custom domain support lets affiliates cloak the link on their own brand.
Track every affiliate link inside systeme.io
Auto-generated unique links, first-party cookie tracking, per-campaign sub-IDs, custom domain cloaking, and anti-self-referral protection all built in. Free plan with no platform commission.
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