Server-side tracking vs cookie tracking: the post-cookie reality

Server-side tracking vs cookie tracking: the post-cookie reality
Hot reminder: if your program still relies only on third-party cookies, you're losing sales you'll never even see.

Safari kills third-party cookies. Firefox kills them. Chrome's been threatening it for years. Cookie-only tracking quietly undercounts your conversions and you can't dispute what you can't observe.

Server-side / postback tracking fires the conversion from the vendor's server, not the browser, so ad-blockers and cookie purges don't erase it.

The tradeoff:
— Cookie: easy to set up, increasingly leaky, browser-dependent.
— Server-side postback: reliable, but you need a network or vendor that supports it and a SubID to match against.

Verdict: ask every program one question, "do you support server-side postbacks?" If the answer is no, assume your reported conversions are a floor, not the truth.