Sub-ID

A sub-ID is a query-string parameter you control, separate from your affiliate tag. The network records the value you assign on every click and every conversion, then lets you slice reports by it. You choose the labelling system; the network just stores it. With a sub-ID, one affiliate program turns from a single revenue number into a per-placement breakdown.

Where the sub-ID parameter lives, by network. Amazon Associates does not have a dedicated sub-ID parameter and instead uses tracking-ID variants on the tag itself (?tag=yourname-yt-20, ?tag=yourname-blog-20). You create up to 100 of these in the Associates dashboard. Awin uses &clickref= (with clickref2 through clickref5 for hierarchical breakdowns). Impact supports subid1 through subid5. CJ (Commission Junction) uses sid. ShareASale uses afftrack. Webgains uses clickref. Daisycon and TradeTracker each have proprietary names but follow the same pattern.

Naming schemes that scale. A disciplined scheme makes the data usable. A common pattern is platform-format-content: yt-rev-xm5 for the Sony XM5 YouTube review, nl-weekly-cookware for the cookware section of the weekly newsletter, blog-best2024-headphones for the headphones round-up post. Keep separators consistent (use -, never spaces or _ mixed in), lowercase only (most networks are case-sensitive), and keep total length under ~40 characters because some networks truncate.

Sub-ID versus <a href="/glossary/click-id" class="font-medium text-ab-violet underline decoration-ab-violet/30 underline-offset-4 transition-colors hover:decoration-ab-violet">click ID</a> versus <a href="/glossary/utm-parameters" class="font-medium text-ab-violet underline decoration-ab-violet/30 underline-offset-4 transition-colors hover:decoration-ab-violet">UTM parameters</a>. Three layers that look similar but belong to different systems. The sub-ID is yours; you choose it and you read it in the network's reports. The click ID is the network's; it assigns one per click and uses it for server-to-server attribution. UTM parameters are Google Analytics' (or your analytics tool's); they tell you which placement sent traffic to your own site, but never reach the merchant. For an affiliate link that goes directly to a merchant, only the sub-ID gives you per-placement revenue data.

Questions sub-IDs let you answer. "Is my newsletter actually outearning my YouTube reviews on the same product?" "Which blog post drives the most Amazon sales?" "Did the pinned-comment placement convert better than the description link?" "Which subject-line variant pulled more conversions on this affiliate offer?" Without sub-IDs you cannot answer any of these from network data alone; you have one bucket per program and have to estimate the rest.

Common mistakes. Spaces and uppercase get URL-encoded or rejected. Renaming a tracking ID after content is published does not retroactively re-tag old clicks. Some networks delay sub-ID reporting by 24 to 72 hours, so testing a new label and checking the dashboard same-day can be misleading. And sub-ID data is your responsibility to back up: most networks only keep 90 to 365 days of granular sub-ID history before rolling it into aggregates.

When to skip sub-IDs. If you have one piece of content per affiliate program, the breakdown adds noise without information. If your sub-ID volume per label is low (fewer than ~20 clicks), the reports will be too sparse to draw conclusions from. For small catalogues, a quarterly review of which programs earn most is sufficient. The sub-ID payoff scales with content volume.