Ever Wondered What a ‘SubID’ Is?


Performance Enhancing SubIDs

If you are reading the HitPath blog right now, the odds are great that you have a high level understanding of affiliate marketing subIDs and how they work. In fact, it’s entirely possible that you invented the concept of subIDs for tracking, and are simply fact-checking my article for your own amusement. After all, our own HitPath Cofounder, Cort St. Paul, invented the concept of pixel-based tracking, so, it’s entirely possible! However, in the interest of all you newbies out there, I’ll provide some background info and describe the ways in which subIDs are utilized by affiliates and networks to segment leads, optimize campaigns, and improve conversions.

SubID Basics

A SubID is a string of alphanumeric characters generated at the end of a redirect URL, which records a user-defined variable. Often abbreviated as SID, CID, MID, TID, depending on the network and platform, affiliates use subIDs to record and track unique user attributes, traffic sources, banners, and/or link placement. In a nutshell, affiliates use subIDs and subID reporting to determine what’s working for them and what isn’t.


While the affiliate controls and defines subID variables for his or her own purposes, the advertiser and network are able to segment traffic based on subID performance without knowing fully what the variables represent. For example, most HitPath clients use subID reporting in order to filter and reject traffic from poorly performing subIDs, while increasing payouts for top performers. Additionally, when you cross-reference subID stats with other variables like campaign id, geo-location, and device id, you can go back to your affiliates armed with solid performance feedback and tweak campaigns accordingly.

Implementation & Limitations

The tricky part of utilizing subIDs is that all platforms, networks, and advertisers tend to have their own way of structuring subIDs within the redirect URL. For instance, HitPath uses the following format, where the network chooses which variables populate c1, c2, and c3:
[TRACKING LINK]&c1=&c2=&c3=

This allows for flexibility in reporting, depending on which metrics are most crucial to both the affiliate and the network. The c variables are designed to be flexible, allowing the most efficient reporting possible, while also letting the affiliate send all proprietary and relevant information. The best way to be sure you’re passing subIDs correctly is to communicate with your affiliates, and if all else fails, contact our amazing 24/7 HitPath Support team.