GA4 Reporting Identity Changed: Why Your User Counts Dropped and How to Fix It

Google quietly changed the rules again. User-Provided Data — things like hashed email addresses — has been removed from GA4's Reporting Identity resolution. If you've noticed a sudden drop in your user counts, this is probably why.

It's not a bug. It's the new privacy-first normal.

(For context on how GA4's identity resolution fits into the bigger picture, see our Complete GA4 Guide.)

What Changed in GA4 Reporting Identity

GA4 uses a system called Reporting Identity to stitch together user sessions and determine how many unique users you have. Previously, this could use four types of data: User-ID (your own logged-in user identifier), Google Signals (data from users signed into Google), Device-ID (browser and device identifiers), and User-Provided Data (hashed emails and phone numbers sent via Enhanced Measurement).

Google has now excluded User-Provided Data from the Reporting Identity chain. Hashed emails and similar identifiers can still be used for advertising audiences and Enhanced Conversions, but they no longer count toward user recognition in your analytics reports.

Think of it like throwing a party where half the guests you only knew by their email RSVP. They're still at the party, but they're no longer allowed in the main hall where you count attendance. Your headcount drops, but the actual crowd hasn't changed.

Why Your GA4 User Counts Might Drop

If your GA4 was relying — even partially — on User-Provided Data to recognize returning users, your reported user counts will drop. This is especially noticeable if you had set up User-Provided Data collection but didn't have a strong User-ID implementation running alongside it.

Here's the disconnect you'll see: your advertising audience sizes in Google Ads may stay the same (since User-Provided Data still works for ads), but your GA4 reports will show fewer recognized users. The same people are there — GA4 just can't identify them as the same person in reports anymore.

Who This Affects Most

E-commerce businesses that collect emails at checkout and use Enhanced Measurement to send hashed emails to GA4. If User-ID wasn't also implemented, those post-purchase users are now harder to track across sessions in your reports.

Lead generation sites that capture form submissions with email addresses. If you were sending hashed emails to GA4 to improve user recognition, that data no longer contributes to reporting — meaning your unique user counts and return visitor metrics lose accuracy.

Businesses with low login rates. If most of your users don't log in (meaning User-ID coverage is low), User-Provided Data was doing more heavy lifting for identity resolution than you might have realized. Its removal will show a bigger impact in your numbers.

The Fix: Strengthen Your User-ID Implementation

With User-Provided Data out of the Reporting Identity equation, User-ID becomes even more critical. It's now the most reliable first-party signal you have for recognizing users across sessions and devices in GA4 reports.

Audit your current User-ID coverage. What percentage of your sessions have a User-ID attached? If it's below 30–40%, you have a significant gap that this change just made worse.

Expand login touchpoints. The more places users authenticate — account creation, checkout, wishlist, saved preferences — the more sessions get a User-ID attached. Look for opportunities to encourage login without adding friction to the user experience.

Ensure User-ID is set correctly in GTM. A surprising number of implementations have User-ID configured but firing inconsistently — only on certain pages, or only after specific interactions. It should be set on every hit where the user is authenticated.

Don't abandon User-Provided Data entirely. It still works for advertising audiences and Enhanced Conversions in Google Ads. Just understand that it's now an advertising tool, not a reporting tool. Keep it in your implementation for ad optimization — just don't rely on it for analytics accuracy.

The Bigger Picture for First-Party Data Strategy

This change is part of a clear trend: Google is tightening the boundary between advertising data and reporting data. What works for ad targeting doesn't automatically work for analytics measurement, and the gap between the two is growing.

(This is closely related to the Consent Mode v2 changes — another area where Google is drawing sharper lines between consent and measurement.)

For businesses, the takeaway is straightforward: your first-party data strategy — particularly User-ID and authenticated user tracking — matters more than ever. The platforms are increasingly restricting what third-party and probabilistic signals can do in reports. Your own data is the foundation that everything else builds on.

If your User-ID setup isn't strong enough to handle this change, now is the time to fix it — before the next privacy update makes the gap even wider.

Frequently Asked Questions

Why did Google remove User-Provided Data from Reporting Identity? Google is tightening the boundary between advertising data and analytics reporting data. User-Provided Data (hashed emails) can still power ad audiences and Enhanced Conversions, but no longer helps identify users in your GA4 reports.

Will my Google Ads audiences be affected? No. User-Provided Data still works for advertising audiences and Enhanced Conversions in Google Ads. Only your GA4 reporting user counts are affected.

What should I do if my User-ID coverage is low? Expand login touchpoints (account creation, checkout, wishlists, saved preferences), audit your GTM configuration to ensure User-ID fires on every authenticated hit, and prioritise authentication across your user experience.

👉 Book a free User-ID audit to check whether your identity resolution is solid enough for GA4's new reality. 🥭