Sub-ID Tracking: Knowing Exactly Which Video, Campaign, or Channel Converts

You run traffic from five places — a YouTube channel, a Telegram group, two landing pages, and a weekly email blast — and your broker's dashboard shows one number: total conversions. You cannot tell whether the video that took eight hours to edit brought in three funded accounts or zero. You cannot tell whether the Telegram group is worth the time you spend moderating it. Without sub-ID tracking, every optimization decision you make is a guess dressed up as a strategy.

Sub-ID tracking solves this by attaching a custom identifier to every tracking link you generate, so the broker's system reports back not just "a conversion happened" but "a conversion happened, and it came from this specific channel, campaign, or piece of content." This article covers how sub-IDs actually work, how to structure them so the data stays useful as you scale, and the mistakes that quietly destroy months of attribution history. For the mechanics of how tracking links, cookies, and postback URLs fit together end to end, see how IB tracking actually works.

What a sub-ID actually is

A sub-ID is a parameter you append to your affiliate link — commonly labeled sub1, sub2, s1, clickid, or similar depending on the platform — that you populate with a value of your choosing. The broker's tracking link does not interpret this value; it simply stores it alongside the click and passes it through the entire conversion chain, so it shows up later in your reporting exactly as you wrote it.

A basic link with no sub-ID looks like:

https://broker.example/ref/YOURCODE

The same link with a sub-ID attached looks like:

https://broker.example/ref/YOURCODE?sub1=youtube-review-2026

Everything after ?sub1= is yours to define. Most platforms that support server-to-server tracking (the mechanism where the broker's server, not the visitor's browser, reports the conversion — see the note below) allow multiple sub-ID slots, often up to five or ten, so you can tag a single click with several independent dimensions at once: which channel it came from, which piece of content, and which audience segment.

Why granularity beats aggregate numbers

An aggregate conversion count tells you that something is working. A sub-ID broken out by channel tells you what is working, which is the only version of that answer you can act on.

Consider two content creators driving the same volume of clicks:

Creator B can act on the data within a week. Creator A is still guessing a year later. This is the entire value proposition of sub-ID tracking: it converts a single opaque number into a decision-ready breakdown.

How to structure your sub-ID taxonomy

The single biggest mistake IBs make with sub-IDs is treating them as a free-text field and improvising a new label every time. Six months in, the data becomes unreadable — dozens of near-duplicate tags (yt, youtube, YT-video, Youtube_new) that a spreadsheet cannot group. Decide the structure before you generate your first link.

A workable pattern for most IBs:

1. sub1 — channel. The traffic source category: youtube, telegram, email, landing-a, landing-b. Keep this list short and fixed; add a new value only when you genuinely add a new channel.
2. sub2 — campaign or content ID. A specific video, post, or send: review-mt5-aug26, weekly-signal-32. This can grow without limit since each value maps to one concrete asset.
3. sub3 — audience or geography (optional). Useful once volume is high enough to segment by region or list, e.g. eu-list, asia-tg.

Lowercase, hyphenated, no spaces, no special characters — some tracking systems silently strip or mangle characters outside a safe set, which corrupts the sub-ID without any error message. Test a new naming pattern with one link and confirm it reports correctly before rolling it out across every campaign.

Where sub-IDs come from in practice

You rarely type sub-IDs by hand for every link. Three common workflows generate them at scale:

• Manual tagging for a small number of evergreen assets — a pinned Telegram link, a fixed landing page CTA. Low volume, low risk of inconsistency if you have a written taxonomy.
• UTM-to-sub-ID mapping. Many brokers accept standard UTM parameters and mirror them into sub-ID fields automatically, letting you reuse the same tagging discipline you already apply to Google Analytics or Meta Ads.
• Dynamic generation via a link shortener or deep-linking tool. For content creators publishing dozens of videos or posts a month, a tool that auto-populates sub2 from the video's slug or upload date removes the manual step entirely and eliminates typos. See link cloaking and deep linking for how this interacts with branded short links and platform bans.

Reading the reports without fooling yourself

Once data starts flowing, the temptation is to declare a winner after the first week. Two things make sub-ID reports misleading if you read them too early or too narrowly:

• Sample size. A channel with 40 clicks and 2 conversions is not meaningfully outperforming a channel with 4,000 clicks and 180 conversions just because the small sample's percentage looks higher. Wait for enough volume before reallocating effort.
• Attribution lag. Forex and prop-trading conversions often complete days after the first click, because KYC drop-off and account funding take time. A channel that looks weak in a same-week report may simply have conversions still pending. Compare full attribution-window cohorts, not partial weeks — see cookie windows and attribution for how the clock actually runs.

Mistakes that quietly break your data

• Reusing the same sub-ID across unrelated campaigns. If promo means three different things across three months, the historical trend line becomes meaningless.
• Changing your taxonomy without archiving the old one. If you rename yt to youtube halfway through the year, your channel totals split in two and neither number reflects the true picture.
• Ignoring case sensitivity. Some systems treat YouTube and youtube as different values. Standardize on lowercase everywhere.
• Tagging at the wrong granularity. A single sub-ID covering "all social media" tells you nothing once you're running five different platforms; a separate sub-ID per platform (and per campaign within it) is what makes the comparison possible.
• Never cross-checking against the raw click log. A tracking pixel or postback that silently fails will make a channel look dead when it's actually a broken integration.

Sub-IDs and postbacks together

Sub-ID data becomes far more powerful when paired with postback URL integration, because a postback lets the broker notify your own tracking system the moment a conversion or funded-account event happens — sub-ID intact — rather than making you log into a dashboard and manually cross-reference numbers. This is the difference between a static monthly report and a live, queryable dataset you can pull into your own spreadsheet or business-intelligence tool. The mechanics of setting this up are covered in postbacks and S2S tracking.

Do sub-IDs work the same way across forex, crypto, and prop-firm programs?

The underlying mechanism is nearly identical — a passthrough parameter attached at click time — but the granularity brokers expose in reporting varies. Prop firms tend to report at the account level (funded, breached, payout), forex brokers at the trade or deposit level, and crypto exchanges at the trading-volume level. Confirm what events your sub-ID reporting actually breaks out before assuming it matches the events you care about.

How many sub-IDs should I actually use?

Most IBs get real value from two to three: channel, campaign or content, and optionally audience segment. Adding a fourth or fifth rarely improves decisions and mostly adds maintenance burden — more slots to keep consistent, more room for a typo to silently orphan data.

Where this fits in your partner decision

Sub-ID support, along with how consistently a partner honors it through redirects and postbacks, is one of the operational details worth checking before you commit meaningful traffic volume to any broker, exchange, or prop firm. It sits alongside commission structure and payout terms as a genuine due-diligence item, not an afterthought — see the IB due-diligence checklist for the full list of what to verify before signing. The Revenika Partner Glossary is a useful starting point for looking up the exact tracking and attribution terms a program's documentation uses, so you know what to ask for before you sign.

Conclusion

Sub-ID tracking turns a single conversion number into a decision-ready breakdown of what is actually working. Fix your taxonomy before you scale, confirm the sub-ID survives the full redirect and postback chain, wait for real sample size before reallocating effort, and cross-check the broker's reporting against your own logs. Get those four things right and every dollar of time or ad spend you put into a channel is backed by evidence instead of a guess.

Frequently Asked Questions

What's the difference between a sub-ID and a UTM parameter?

A UTM parameter is a web-analytics convention (Google Analytics and similar tools read utm_source, utm_campaign, etc.) used to tag traffic for your own analytics platform. A sub-ID is the affiliate-tracking equivalent, read by the broker's own attribution system rather than a general analytics tool. Some brokers map UTM values into sub-IDs automatically; others require you to set the sub-ID field separately. Always confirm which is which for a given program.

Can a broker fabricate or manipulate sub-ID data?

Any reporting system a partner fully controls carries some trust dependency, which is exactly why cross-checking against your own click logs and, where available, conversion tracking from a second, independent source matters. This is not an accusation against any specific broker — it is a basic control any serious IB should have in place regardless of how much they trust the partner.

Do I need special software to use sub-IDs, or can I just add them to a link manually?

You can add sub-IDs manually to a handful of links with no tooling at all. Once you're generating dozens of links a month across multiple channels, a dedicated deep-linking or link-management tool that auto-populates sub-IDs consistently becomes worth the cost, mainly because it eliminates the typo and inconsistency risk that breaks aggregation later.

Why does my sub-ID show up blank in the broker's report even though I added it to the link?

The most common causes are: the redirect chain dropped the parameter at an intermediate hop, the character set used in the value wasn't accepted by the tracking system, or the click never actually completed the full journey to the broker's landing page. Test with a single simple value (letters and hyphens only) and verify it appears correctly before troubleshooting further.

Should I use the same sub-ID structure across every broker I work with?

Yes, where the platforms allow it. A consistent taxonomy across partners means you can compare channel performance across your entire portfolio in one spreadsheet instead of reconciling different naming conventions per broker — a real time cost as your list of partners grows.