Sub ID

A Sub ID is a custom tracking parameter that affiliates attach to their affiliate link to break down performance at a granular level. Instead of seeing aggregate conversions from one tracking link, Sub IDs let affiliates tag individual traffic sources -- such as a specific banner, landing page, email campaign, or social media post -- so they can analyze which exact placement drove each conversion. This data flows through the operator's tracking system alongside the standard postback and attribution data.

Affiliates use Sub IDs to run more effective optimization. For example, a media buyer running paid campaigns across multiple ad networks can assign a unique Sub ID to each network, creative, or audience segment. When conversion rate data comes back tagged with these Sub IDs, the affiliate can see exactly which combinations are profitable and which are not -- without needing a separate tracking link for every variation. Most affiliate programs support multiple Sub ID slots (commonly labeled sub1, sub2, sub3), enabling multi-dimensional analysis.

For operators, Sub IDs provide transparency into how affiliates drive traffic. When reviewing affiliate quality or investigating suspicious patterns, Sub ID data reveals whether an affiliate is sending traffic from legitimate placements or questionable sources. Combined with s2s tracking, Sub IDs create a detailed picture of the entire conversion path from click to customer, benefiting both the affiliate and the operator.