GA4 Conversions Not Counting? Here's Why (And How to Fix It)

You did everything right — set up the event, marked it as a key event (conversion), and waited. But GA4 shows zero conversions. Or the numbers are way lower than expected. Or conversions appear in GA4 but not in Google Ads.

Here are the 9 reasons this happens, ordered by how frequently we see them in our audits.

1. The Event Isn't Actually Firing

Frequency: Found in 34% of cases.

Before debugging conversion tracking, verify the underlying event actually fires. Open GA4 DebugView or the Realtime report and trigger the conversion action. If you don't see the event, the problem is with your tag or trigger — not the conversion setting. Check GTM for trigger conditions, tag firing order, and consent blocking.

2. "Key Event" Toggle Not Saved Properly

Frequency: Found in 18% of cases.

Navigate to Admin → Events and find your event. The toggle in the "Mark as key event" column must be blue/on. If you marked an event as a key event but used a slightly different event name (e.g., Purchase vs purchase — GA4 is case-sensitive), you've marked the wrong event.

3. 24-72 Hour Processing Delay

Frequency: The most common false alarm.

GA4 conversion data can take 24 to 72 hours to fully process and appear in standard reports. The Realtime report shows conversions within minutes, but standard reports and Google Ads imports have processing delays. If you just set up a conversion, wait 72 hours before troubleshooting.

4. Conversion Counting Method

Frequency: Common for e-commerce.

GA4 has two counting methods for key events:

• Once per session: Only the first instance counts. If a user submits a form 3 times, GA4 counts 1 conversion.
• Once per event: Every instance counts. Each of the 3 form submissions counts as a separate conversion.

For lead gen events, "once per session" is usually correct. For purchases, use "once per event" (each transaction is a separate conversion). Check this under Admin → Events → [your event] → Counting method.

5. Consent Mode Blocking Conversion Hits

Frequency: Found in 28% of properties with Consent Mode.

If analytics_storage is denied, GA4 doesn't record the full event — it sends a cookieless ping. The event still fires, but conversion attribution may be limited. If ad_storage is also denied, the conversion won't be usable for Google Ads optimization at all.

Check: Open your browser's Network tab and look for requests to google-analytics.com/g/collect. If you see gcs=G100 in the payload, both analytics and ad storage are denied. gcs=G111 means both are granted.

6. Data Filter Excluding Conversion Traffic

Frequency: Found in 8% of cases.

If you have an active data filter (not just testing mode), it may be excluding the IP addresses or traffic sources where conversions occur. This is especially common when the conversion happens on a staging server or development environment whose IP is filtered.

7. Event Name Mismatch

Frequency: Found in 15% of cases.

GA4 event names are case-sensitive. If your GTM tag sends generate_lead but you marked Generate_Lead as a key event, they're treated as different events. Always use snake_case and verify the exact event name in DebugView.

8. Google Ads Link Missing or Misconfigured

Frequency: Causes "conversions show in GA4 but not in Ads".

For conversions to appear in Google Ads:

• GA4 and Google Ads must be linked (Admin → Google Ads Linking)
• The conversion must be imported in Google Ads (Google Ads → Goals → Conversions)
• Auto-tagging must be enabled in Google Ads
• Personalized advertising must be enabled in the link settings

9. E-commerce Value Not Sent

Frequency: Common for purchase events.

If your purchase event fires but shows 0 revenue, the value and currency parameters are likely missing or formatted incorrectly. The value must be a number (not a string like "$99.00"), and currency must be a valid ISO 4217 code (e.g., USD, EUR, SEK).

Key Takeaways

• Always verify the underlying event fires before troubleshooting the conversion setting.
• Wait 72 hours for conversions to appear in standard reports — use Realtime for immediate checks.
• Event names are case-sensitive. purchase ≠ Purchase.
• Check consent mode status — denied analytics storage limits conversion tracking.
• For Google Ads, you need: link + import + auto-tagging + personalized advertising.