The short version: Enhanced conversions for leads works by taking the email address or phone number someone submits on your form, hashing it before it ever leaves the browser, and sending that encrypted data to Google. Google uses it to match the submission against its own user database — the accounts people are actively signed into — so it can attribute the conversion even when cookies are unavailable or were never set. It's not the same thing as offline conversion tracking, and if you're running lead gen campaigns seriously, you'll eventually want both.
What's Actually Happening Under the Hood
A standard Google Ads conversion tag is pretty blunt: someone reaches your thank-you page, the tag fires, and Google records a conversion event. That's the whole story.
Enhanced conversions for leads adds a second layer. When the form submits, the tag captures whatever personal data the user just entered — typically their email address — runs it through SHA-256 hashing to produce an unreadable string, and sends that hash to Google alongside the conversion event. Google then attempts to match that hash against its database of logged-in users. When the match works, Google can tie the conversion back to an ad click even if a cookie wasn't available: the person switched devices, cleared their browser, or declined tracking through a consent banner.
The downstream effect is a more complete conversion record, which gives Smart Bidding more accurate data to work with over time.
Enhanced Conversions vs. Offline Conversion Tracking: Not the Same Thing
This is the distinction Google's own documentation tends to blur, and it causes real confusion for anyone setting this up for the first time.
Enhanced conversions for leads is a browser-side event. It fires at the moment of form submission, in real time, on your website. Its job is to improve attribution for the lead event itself.
Offline conversion tracking runs on a completely different timeline. You capture the GCLID — Google's click identifier — when someone first lands on your site from an ad, store it in your CRM alongside the lead record, and then upload conversion data back to Google after something meaningful happens downstream: a discovery call gets booked, a contract gets signed, an opportunity reaches a certain stage. It tells Google which ad clicks actually turned into revenue, not just which ones turned into form submissions.
These two tools address different parts of the funnel. If a lead submitting a form is the outcome you care about, enhanced conversions helps you track that accurately. If you care about what happens after the form submission — whether the lead actually became a customer — offline conversion tracking is what closes that loop. For most B2B lead gen setups, you want both running simultaneously.
Why CRM-Based Enhanced Conversion Imports Sometimes Show Nothing
This is a particularly frustrating failure mode because everything looks like it's working. Your CRM integration reports successful imports. No errors show up anywhere. But your conversion columns stay empty.
The issue is that CRM-based enhanced conversions aren't standalone. They need a browser-side anchor event — a conversion tag that fires on your website at the moment of form submission — before the downstream CRM data can be matched and attributed. Without that browser-side event, Google has no click to attach the hashed email to. The CRM data arrives, Google looks for a corresponding browser event to match it against, finds nothing, and quietly discards it.
The fix is to run the website tag and the CRM integration in parallel, not as alternatives. The website tag fires at submission and creates the attribution anchor. The CRM data fills in what happened later. Each serves a different purpose.
Three Ways to Set It Up
Using the Google Tag directly
Go to Goals > Conversions > Settings in Google Ads and enable enhanced conversions for leads. Select Google Tag as your implementation method. From there, you'll add an enhanced_conversion_data object to your existing tag that includes the relevant form fields — email, phone, or both. Verify the setup with Tag Assistant before calling it done.
Using Google Tag Manager
Open your existing conversion tag in GTM and look for the option to include user-provided data. You'll create a User-Provided Data variable that maps to your specific form fields, then publish the updated container. Tag Assistant can confirm whether the data is being captured and sent correctly.
Using a CRM integration
HubSpot, Salesforce, and several other platforms offer native Google Ads integrations that can push enhanced conversion data. Treat this as a supplement to your website tag, not a replacement for it. The CRM integration is valuable for sending downstream lead quality signals — but it depends on the website tag having already created the attribution anchor.
If GTM Says the Tag Isn't Firing on Your Form
A few things to check before going in circles:
The form uses AJAX. If the form submits without a full page reload, GTM's built-in Form Submission trigger won't fire. You need either a Click trigger on the submit button or a custom event trigger that the form fires through its own success callback.
The trigger still points to an old URL. If your thank-you page URL changed at any point, update the trigger to match.
The form lives inside an iframe. GTM can't reach into iframes — the tracking needs to be implemented directly within the iframe's source page.
Auto-tagging is turned off. Enhanced conversions requires auto-tagging to be enabled at the account level. Without it, GCLIDs don't get passed on ad clicks, and the whole attribution chain breaks.
What to Expect From Bidding Performance
Setting up enhanced conversions won't produce an immediate lift in your campaigns. Google states that it can take up to 75 days before enhanced conversion data meaningfully shapes how Smart Bidding makes decisions. The data needs time to accumulate and be factored into the model.
It also won't inflate your conversion numbers. Enhanced conversions doesn't create new conversion events — it improves the accuracy of attribution for conversions that were already happening, and recovers some that were previously lost to cookie gaps. Think of it as cleaning up the signal, not amplifying it.
The practical implication: set this up before you need it. Implementing it mid-flight on a struggling campaign and expecting an immediate turnaround will lead to disappointment.
FAQs
What personal data actually gets sent to Google?
Only hashed versions of whatever the user submitted: email, phone number, name, and address fields. The hashing (SHA-256) happens in the browser before transmission, so Google never receives the raw information — only an encrypted string it can attempt to match against its own database.
Is auto-tagging required?
Yes. Auto-tagging is what allows Google to pass GCLIDs through ad clicks. Enhanced conversions needs that GCLID to connect hashed user data back to the original click. If auto-tagging is off, the whole mechanism fails.
Does this only work with Smart Bidding?
No — enhanced conversions improves attribution accuracy regardless of your bidding strategy. That said, it has the most measurable impact when paired with Smart Bidding strategies like Target CPA, Target ROAS, or Maximize Conversions, because those algorithms actively use conversion data to make real-time decisions.
What's the difference between enhanced conversions for leads and enhanced conversions for web?
They're designed for different conversion types. Enhanced conversions for web is built around e-commerce purchases — it matches transaction data. Enhanced conversions for leads is built for form submissions where the goal is capturing a lead rather than completing a sale.
Does using enhanced conversions create GDPR compliance issues?
The data is hashed before it leaves your site, which means raw personal information is never transmitted. That said, you're still collecting and processing user data, which typically needs to be disclosed in your privacy policy and covered by your consent setup. If you're using a consent management platform, make sure it's configured to allow the enhanced conversion tag to fire for users who have given consent — blocking it for everyone will undermine the whole setup.
If you're tracking form submissions but not getting them back into Google Ads cleanly, FormTrackr handles GCLID capture and offline conversion uploads — so the signal Google needs to optimize is always current.