What is an Affiliate Link?

An affiliate link (tracking link, referral URL) is a partner-specific URL issued by an affiliate network or advertiser so a click can be logged and an attribution window opened. The link is not the offer itself and not “any product URL”: the offer defines product, GEO, and payout; the link is the instrument that records the click, cookie, and click ID.

In affiliate marketing a partner without their own link earns no commission even if the user buys: the network cannot tell whose click it was. Marketplace copy (“Amazon / AliExpress / Shopee affiliate link”) uses the same idea (partner ID in the URL + cookie) on different infrastructure than a CPA tracking URL.

URL anatomy

A typical CPA-network link points at the network or a tracking domain and carries IDs:

offer ID / campaign ID — which offer to open;
affiliate ID — who earns the commission;
click ID — a per-click key (issued by the network or the partner’s tracker);
sub ID (sub1–subN) — the buyer’s labels: creative, placement, GEO split;
sometimes UTMs for analytics on your own landing.

Schematic example: https://go.network.example/click?o=1842&a=991&sub1={clickid}&sub2={creative}. Macros are filled by the tracker or the ad account. Marketplace links are shorter — ?tag=partner-20 or a similar tag — with the same job: who drove the click.

What happens on click

The user hits the link → the network or tracker writes the click (time, IP/GEO, user-agent) → sets an affiliate cookie and/or stores a click ID → redirects to the landing or offer page. If a conversion later falls inside the cookie duration, the network matches cookie or click ID and fires a postback. Without a click ID in the offer URL, postback cannot join conversion to click — orphan revenue for the advertiser, not the buyer.

In mobile and in CPA after cookie restrictions, server-to-server click IDs often matter more than a browser cookie. The link is still required: without it no ID is created.

Sub ID vs click ID

Click ID is one per click and required for attribution. Sub IDs are your in-campaign labels: the tracker uses them for EPC and to cut a losing creative. Colloquially “put a subid on the affiliate link” often means both layers at once. An empty macro (sub1={ad_id} on a buy with no dynamic params) pollutes reports; the link still functions.

Marketplace vs CPA

Amazon Associates, AliExpress, cashback and coupon programs issue a link to a product or category: CPS commission, a short cookie window (often 24 hours). A CPA network issues a link to an offer paid on lead, FTD, or install. A smart link is one URL that rotates several offers. The advertiser’s raw URL without partner parameters pays no commission, even on “the same site.”

What the link is not

Cookie stuffing plants an affiliate cookie without a click on the link (hidden iframe, extension). That is fraud, not “another link format.” A legitimate link implies a user-initiated click. Do not confuse this with a hold period: hold counts days from conversion to payout, not how long the cookie lives after the click.

Common breakages

Pasting the “clean” landing URL from the offer preview — no affiliate ID.
A redirect or pre-lander stripping the query string so the click ID never reaches the network.
One shared link for a whole team with no per-buyer subs — stats cannot be split.
Mixing UTMs and network params until a signature fails or the URL exceeds length limits.