Quick Answer: Your website code needs exactly one thing, the Google Tag Manager container snippet. Every other tag (the Google Tag, your Google Ads Conversion tag, the Conversion Linker, GA4 event tags) lives inside GTM. The AW tag is legacy AdWords code and can be removed. Set up in this order: GTM on the site, Google Tag inside GTM, Conversion Linker, GA4 event tags, then Google Ads Conversion tags for the actions that matter.
Why You Have Four Tags and No Idea Which One Is Working
If you open your site's source code and find a Google Tag, a GTM snippet, a GA4 tag, and an old AW tag all stacked on top of each other, you're not alone. This is the most common tracking mess I see. It usually happens the same way. You followed Google's setup wizard once. Then a plugin added its own gtag. Then you installed GTM because a tutorial said to. Nobody ever removed anything.
The result is a setup where you can't answer the only question that matters. When someone converts, which tag reports it, and does it report it once or three times?
That fear is justified. Stacked tags cause double-counting. Your Google Ads conversion column inflates, Smart Bidding optimizes toward phantom conversions, and your GA4 numbers stop matching anything. You end up spending real money on decisions made from data you can't trust.
What Each Tag Actually Is
Before the fix, a plain-English rundown.
The Google Tag (gtag) is Google's unified measurement tag. One Google Tag now feeds both GA4 and Google Ads. This replaced the old separate setup.
Google Tag Manager (GTM) is not a tracking tag at all. It's a container. It holds your other tags and controls when they fire. GTM is the only thing that belongs in your website code.
The GA4 tag sends data to Google Analytics. Inside GTM this is your Google Tag configuration plus GA4 event tags for the actions you care about.
The Google Ads Conversion tag reports conversions directly to Google Ads. It needs a conversion ID and conversion label from your conversion action in the Ads interface.
The Conversion Linker stores click data (like the GCLID) in a first-party cookie so your Ads conversions attribute correctly.
The AW tag is the old AdWords tag. If you see AW hardcoded on your site alongside the others, it's a leftover. Its job is now handled by the Google Tag.
The Fix: One Container, Three Core Tags, In This Order
Here is the full setup sequence. Do it in this order and you get accurate conversion tracking without repeat hits.
Step 1: Strip the site code down to GTM only
Remove every hardcoded gtag, GA4 snippet, and AW tag from your site's code and plugins. The only Google code on the page should be the GTM container snippet. If a plugin insists on injecting its own gtag, disable that feature. Two tags firing the same event is how double-counting starts.
Step 2: Add the Google Tag inside GTM
Create a Google Tag in GTM with your tag ID, set to fire on all pages. This one tag handles the base measurement for both GA4 and Google Ads. You do not need a separate GA4 configuration tag anymore.
Step 3: Add the Conversion Linker
Create a Conversion Linker tag, fire it on all pages. It takes 30 seconds and it's the step everyone skips. Without it, GCLID data can get lost and your Ads conversions under-report.
Step 4: Create GA4 event tags for your key actions
For each action you want to see in GA4 (form submit, purchase, call click), create a GA4 event tag with a trigger for that action. These are for your reporting and analysis.
Step 5: Create Google Ads Conversion tags for the actions you bid on
In Google Ads, create a conversion action and grab the conversion ID and conversion label. In GTM, create a Google Ads Conversion Tracking tag with those values, using the same trigger as your GA4 event. Track conversions natively in Ads this way instead of importing them from GA4. Native Ads conversions attribute better, report faster, and give Smart Bidding cleaner signals. Data should flow from Google Ads into GA4, not the other way around.
Step 6: Verify nothing double-fires
Open GTM Preview mode and Tag Assistant, then complete a test conversion. Watch the tag firing log. Each tag should fire exactly once per event. If you see the same conversion tag fire twice, check for a duplicate trigger or a leftover hardcoded snippet you missed in Step 1.
That's the whole stack. One container in the code. A Google Tag, a Conversion Linker, GA4 event tags, and Ads conversion tags inside it. Nothing else.
If you want the full picture of what clean conversion signals look like once the tags are sorted, including which conversion actions to mark primary and how to tell if Google is actually getting good data, Stop Flying Blind covers it step by step. It's my free course at freak.marketing/learn/courses/stop-flying-blind.
FAQ
Why don't my Google Ads and GA4 conversion numbers match?
They never will, and that's normal. Google Ads and GA4 use different attribution models and different counting windows. Ads credits the click date, GA4 credits the conversion date. Pick native Ads conversions as your source of truth for bidding decisions and treat GA4 as directional.
Should I import GA4 conversions into Google Ads instead?
No, not if you can tag natively. GA4 imports add delay and lose attribution detail. Use the Google Ads Conversion tag in GTM for anything Smart Bidding will optimize toward. The main exception is when your conversion only exists as a GA4 event you can't replicate, like an engagement metric.
Do I still need the AW tag for remarketing?
No. Remarketing audiences now build through the Google Tag and your linked GA4 property. If an old AW remarketing tag is still hardcoded on your site, remove it along with the rest in Step 1.
How do I know if I've been double-counting conversions?
Check your conversion action in Google Ads for a sudden inflation compared to actual leads in your CRM or inbox. Then run Tag Assistant on your conversion page. If two tags with the same conversion ID fire on one event, or a hardcoded gtag fires alongside your GTM tag, you've found it.