Fathom Analytics vs Google Analytics: Who Each Count Serves

The short answer: if Google Ads bids on your conversions, GA4 stays, behind consent, and the only question is whether to add Fathom Analytics beside it. If nothing in your budget depends on Google's bidding and your sites together stay under 100,000 pageviews and events a month, Fathom's $15 plan, which covers 50 sites, can be the only count you keep (checked on 26 October 2026 on the Fathom pricing page). Google Analytics is free of charge and built to work with Google's advertising products; Fathom charges for the software and describes its counting as cookieless, which is the vendor's description of its own script, to check with counsel rather than treat as a verdict.

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Check these against your own property first:

1. Add events to pageviews before picking a tier. For example, 70,000 pageviews and 12,000 custom events make 82,000 a month, inside Fathom's $15 tier for 100,000; yearly billing gives two months free, so the year costs 10 x $15 = $150, using the pricing page, which says custom events count towards the allowance.
2. Bring the history you have. Fathom's GA4 comparison page says its importer supports GA4, that what it can import depends on Google's API, and that Universal Analytics data Google already deleted cannot come back. Check the imported months against GA4 before you remove anything.
3. Expect two totals, and write down why. The same page lists visit definitions, bot filtering, consent settings, blocked requests and time zones as reasons the tools disagree. Record both weekly for four weeks; the ratio to watch is set out in consent-friendly EU analytics.

How each count is made

Read on 26 October 2026: Fathom's pricing page, compliance overview, data isolation page, GA4 comparison and Luna announcement; Google's cookie usage, Consent Mode overview, EU data and privacy, data sampling, data retention and MCP server pages.

The three differences that matter

What counts as one visitor

Fathom builds a signature per site with a salt that rotates at midnight UTC, so a returning person gets a new signature each day, per its salts and hashes page. GA4 recognises a returning browser for as long as its cookie lasts, 2 years by default, although Google's cookie article notes browsers cap first-party cookies for people who do not return: 400 days in Chrome, 7 in Safari. Fathom's visitor figure answers "how much traffic"; GA4's user figure tries to answer "how many people", with gaps the browser decides.

What a refusal does to each count

Article 5(3) of the ePrivacy Directive allows storing or reading information on a visitor's device only with consent given after clear and comprehensive information, apart from what is strictly necessary for a service the user asked for. GA4's cookies sit squarely in that rule, and Google's Consent Mode leaves obtaining consent to you: Basic mode sends nothing until the visitor chooses, Advanced sends cookieless pings while consent is denied. Fathom's homepage says it is GDPR, ePrivacy and PECR compliant; its own compliance overview adds that cookie-free does not automatically mean outside device-access rules. The EDPB's Guidelines 2/2023 read Article 5(3) as reaching beyond cookies. Ask counsel which of these applies to your set-up.

Where EU traffic goes

Both route it through Europe first. Fathom strips EU visitors' IP addresses on EU servers and stores the anonymised record on its US servers, per its data isolation page. Google says GA4 collects EU traffic through EU servers, drops IP addresses there, and forwards the data for processing, per its EU data page. Fathom's data isolation table marks Google Analytics as not processing EU traffic in the EU, which Google's page contradicts; read the two side by side.

What it costs

Checked on 26 October 2026 on the Fathom pricing page and Google's Analytics page. Fathom's plans include 50 sites, with packs of 50 more at $10 a month, and yearly billing gives two months free; there is no free plan. Google sells Analytics 360 through its sales team.

One AI step: Luna asked, a person checking

Fathom's assistant, Luna, answers from Fathom's documentation and reads your stats only after you click Allow. Ask it "Where do my signups come from?" and it breaks the signup event down by referrer, UTM source or entry page. A person then sets the top three sources beside GA4's key event report for the same dates and time zone. Differences in direct traffic are expected; a source that leads in one tool and is missing from the other is a tagging fault to fix before either report goes to anyone. Fathom's announcement says AI can be wrong and that a click on Escalate hands the chat to a person on its support team.

Choose Fathom Analytics if the job is

• Traffic, referrers, campaigns and conversions for content or lead-generation sites, without building reports.
• Running many sites from one account, as an agency or a group with several brands.
• A second count beside GA4 that does not depend on the consent banner's answer, once counsel agrees.

Choose Google Analytics if the job is

• Feeding conversions to Google Ads or Search Ads 360 bidding.
• Explorations, audiences and user-level analysis built on persistent identifiers.
• Analytics with no licence cost.

Free first, and the setting Google turns on

GA4 costs nothing, and Fathom's live demo costs nothing to click through. Before paying for either layer, write down the three numbers someone reads every week and check whether GA4's standard reports already answer them.

Then open GA4's regional settings. Google's EU data page says Analytics collects granular location and device data by default, and that switching it off for a region significantly reduces modelled conversions in linked Google Ads and Search Ads 360 accounts: the default is set for the ad model, and switching it off trades some of Google's modelling for less data about your visitors. Make that choice deliberately rather than inherit it.

If the two counts agree on traffic and still disagree about which campaigns worked, the question has become causal, and a causal attribution tool such as Causality Engine is designed for it (disclosure: I founded it).

FAQ

Can Fathom replace GA4 when the business runs Google Ads?

Fathom's own GA4 comparison says GA4 may be the better fit if your work relies on its advertising integrations. Run Fathom beside it rather than instead of it.

Does Fathom remove the need for a cookie banner?

Fathom's pricing page lists "No cookie banners required"; its compliance overview says cookie-free does not automatically mean outside device-access rules. The banner also still covers every other tag on the site, from ad pixels to chat widgets.

Can I import my GA4 history into Fathom?

Yes, GA4 only, through its importer; Fathom's GA4 comparison says to check the imported results before removing your previous setup and to avoid overlapping imported dates with data Fathom has already collected.