Google Ads Enhanced Conversions for PrestaShop: a plain guide

If Google Ads keeps telling you a campaign earned fewer sales than your PrestaShop back office records, Enhanced Conversions are likely the missing piece. They are Google's mechanism for recovering attribution that cookie restrictions destroy — and for a store owner, they are far simpler than the name suggests.

This guide explains what Enhanced Conversions are, the data they use, the click IDs that make them work, and why they matter for your bidding. It is written so you can understand the moving parts even if you have never opened a tag manager.

What Enhanced Conversions actually are

When someone clicks a Google ad and later buys, Google needs to connect the sale back to the click. Traditionally that link relied on cookies. As browsers and Apple's ITP restrict cookies, the link breaks and conversions go unattributed — the sale shows up in your store but not against the ad that drove it.

Enhanced Conversions rebuild the link using first-party data you already hold — the customer's email, and optionally phone, name, and address. That data is hashed and sent alongside the conversion, letting Google match it to a signed-in Google account that clicked your ad.

The practical result is that conversions cookie-only tracking would have lost come back into view, credited to the right campaign. It is one of the highest-leverage changes a Google Ads advertiser can make right now, and unlike many tracking upgrades it pays off quickly because Google starts using the recovered data as soon as it arrives.

Hashed first-party data and SHA-256

The word “hashed” is what makes this privacy-safe. Before any personal data leaves your store, it is normalised — lower-cased, trimmed, formatted to a standard pattern — and then run through SHA-256, a one-way function that turns an email into a fixed string of characters that cannot be reversed back into the email.

Google hashes its own account data the same way and compares the hashes. A match means attribution; a non-match reveals nothing about the customer. Done correctly, you never transmit a readable email or phone number — only its irreversible fingerprint.

Normalisation matters as much as hashing: "Jane@Example.com " and "jane@example.com" must produce the same hash or the match fails, which is why consistent formatting before hashing is essential. PrestaSignal performs this hashing server-side, so raw PII never reaches the browser. Our privacy & data page details exactly what is sent.

gclid, gbraid, and wbraid

Click IDs are the other half of the match. When someone clicks your ad, Google appends an identifier to the landing URL. gclid is the classic Google Click Identifier, used for most traffic. gbraid and wbraid are newer, privacy-preserving click IDs introduced for iOS traffic — wbraid for web-to-app and app-to-web journeys, gbraid for app-related contexts — designed to work within Apple's restrictions where the old gclid cannot.

A robust setup captures whichever click ID is present on the landing page and passes it with the conversion. Miss them, and you forfeit a major attribution signal on exactly the iOS traffic that is hardest to track in the first place.

Combined with hashed first-party data, the click ID gives Google two independent ways to credit the sale to the right campaign — one based on the click, one based on the customer's identity.

Why Smart Bidding benefits most

Enhanced Conversions are not just a reporting fix — they make your bidding smarter. Google's Smart Bidding strategies (Target ROAS, Maximise Conversions, and similar) learn from conversion data. The more accurate and complete that data, the better its predictions and the better your results.

When you recover the 20-40% of conversions that cookie loss was hiding, Smart Bidding finally sees the true value of each click, keyword, and audience. It stops underbidding on campaigns that were quietly profitable and reallocates budget toward what actually works.

This is the part merchants underestimate. Better data does not just make the dashboard prettier — it changes how the algorithm spends your money, often improving real-world ROAS without you touching a single bid.

A word on accuracy and conversion value

For Smart Bidding to bid well, the conversion value you send has to be right, not just present. Send the tax-included total the customer actually paid so Google optimises toward real revenue rather than an understated subtotal.

It is also worth using a deterministic identity for each conversion — derived from the order reference — so a reloaded confirmation page does not register the same sale twice. Duplicate conversions distort Smart Bidding just as badly as missing ones, teaching the algorithm that certain clicks are twice as valuable as they really are.

Clean inputs — accurate values, no duplicates, strong match signals — are what turn Enhanced Conversions from a checkbox into a genuine performance lever. It is the difference between ticking a box in the Google Ads interface and actually feeding the bidding algorithm the truth about your business.

Setting it up on PrestaShop

A clean setup sends each purchase conversion to Google Ads with the tax-included value, the conversion ID and label, the captured click ID (gclid, gbraid, or wbraid), and the hashed first-party data — all from the server, so nothing depends on the browser surviving the checkout.

Notably, this does not require the Google Ads API, OAuth, or any upload pipeline. The conversion ID and labels plus hashed data and a click ID are enough, which keeps the setup simple and robust.

PrestaSignal wires this through a self-hosted sGTM container alongside your GA4 tracking and Meta CAPI, hashing PII before it leaves your store and reusing the same deterministic event identity used everywhere else. To see how much attribution your account is currently missing, book a teardown.