Affiliate marketing rests entirely on one thing: reliably measuring a conversion and attributing it to the right partner. When a conversion is lost, the partner gets no commission, loses trust — and your reporting is off. Here's how server-side solves it.
Why client-side affiliate measurement fails
A classic affiliate pixel / tag runs in the browser, so it's weakened by ad-blockers and Safari ITP like any other measurement. Lost conversions mean unpaid commissions and inaccurate reporting — a fundamental trust problem in the affiliate world.
How server-to-server (S2S) helps
- The conversion gets through even past an ad-blocker. Instead of a client-side pixel, the conversion is sent straight from the server to the affiliate network via its postback endpoint.
- Accurate attribution to the partner. The partner's click reference is preserved, so the commission goes to the right one.
- Consistent reporting. Network data matches your store.
An example of a specific network (Awin) is covered on the platform page; the general click ID principle is in what GCLID and click IDs are.
What to watch
- Watch for attribution theft by coupon sites — see measuring discount codes.
- Send the real order value and handle returns so commissions are correct.
- Deduplicate if you send the conversion via multiple paths.
Summary
In affiliate marketing, what matters is whether a conversion is reliably measured and attributed to the right partner. Server-to-server tracking saves commissions even where client-side fails — protecting partner trust and your reporting accuracy. More in the complete guide.