If your Google Ads dashboard says 60 conversions, GA4 says 41 and your front desk counted 28 real enquiries, you do not have a reporting problem. You have a tracking problem, and budget is being moved on the wrong number. This guide fixes the setup in order, then shows the one check that tells you whether to trust it.
Why your GA4 and Google Ads numbers never match
GA4 and Google Ads count differently. GA4 credits a conversion to the session's source, Google Ads credits the ad click, and each uses its own dating and window. A small gap is normal. A big gap usually means a conversion is counted twice, or not at all.
Three causes explain most of the gap:
- Attribution. Attribution decides who gets credit. GA4 can split credit across channels; Google Ads credits the ad that was clicked. The same customer legitimately appears in both with different credit.
- Dates and windows. Google Ads dates a conversion to the day of the ad click, while GA4 dates it to the day the event happened. A lead who clicks on Friday and books on Monday sits in different days in each report.
- Double tagging. The same form fill is sent by a GA4 tag and a separate Google Ads tag, and both are set to count. This one inflates Ads and is the most common culprit.
Two smaller ones: a visitor who declines cookies may not be measured the way an accepting one is (consent settings change what each tool can see), and a blocked or broken tag drops events silently. Google's own guidance gives no figure for a "normal" gap, so be suspicious of anyone who does. What matters is whether both tools tell the same story against your own records, which is what the final step checks.
Step 1: decide the one action that counts
Pick the action that means a real customer is near: a booked appointment, a submitted quote form, a paid order, a WhatsApp conversation started. Name it once. If you count page views or button hovers as conversions, Google will chase them and your costs will look good while sales do not.
Decide this before touching any tag, and write it on paper. Examples:
- Clinic: a confirmed appointment request (the thank-you step), not a click on the booking button.
- Real estate developer: a site-visit request submitted, with a phone number.
- D2C store: a completed purchase, with order value.
- School: an admission enquiry form submitted.
- Home-services firm: a call from the ad or a quote request.
You may have a few such actions. That is fine, but rank them. In Google Ads, a Primary conversion action is used for bidding and counted in the Conversions column; a Secondary one is observed but does not steer bidding. Make only the action that equals a customer primary. A phone-number tap can be secondary; a booked visit should be primary.
Step 2: mark it as a key event in GA4
In GA4, a key event is an event you flag as important to your business. Send the event with Google Tag Manager or gtag, confirm it appears in DebugView, then mark it a key event in Admin. Key events were called conversions in GA4 before 2024.
Google defines a key event as one that measures an action particularly important to the success of your business. Any event you collect can become one.
Create and mark the event
Fire the event from the success moment
In Google Tag Manager, trigger it on the form success (the thank-you URL or the form's own success event), not on the button click. A click is an attempt; success is an enquiry.
Name it in plain words
Use GA4's recommended names where one fits:
generate_leadfor an enquiry,purchasefor an order, or a clear custom name such asbook_appointment. Keep the exact spelling consistent everywhere; Google notes that event names must match when you set conversions up in both products.Test before you trust it
Open GA4 DebugView, submit a real test, and watch the event arrive once with its parameters. Check Realtime too.
Mark it a key event
In GA4 Admin, open Events, find the event and switch on Mark as key event. A new event may need to fire once and appear in the Recent events list first.
Google's help pages cover both how key events work and how to create or modify them.
Step 3: link Google Ads and import the event
Link your Google Ads account to the GA4 property, then in Google Ads create a conversion from a Google Analytics event and import the key event. Mark it Primary only if it should drive bidding. Do not also keep a separate Google Ads tag counting the same action, or you will count it twice.
Do the link first. In GA4 Admin, open Product links and choose Google Ads links, then pick the account. Google lists the conditions: you need suitable roles in both products, and to import conversions you also need auto-tagging turned on in Google Ads. Google's linking guide has the current screens.
Then import. In Google Ads, open Goals, go to the conversions summary, choose to create a conversion action, pick the Google Analytics property and select the key event. Google describes the path in its page on creating conversions from Google Analytics events; menus move often, so follow the destination, not the click order.
Google says you can use both approaches at the same time. Both is fine for different actions. For the same action, make sure only one of them is set to count as a primary conversion. A GCLID that gets stripped by a redirect also breaks attribution, so test the landing URL end to end.
Step 4: send better data back with enhanced conversions
Enhanced conversions let you send hashed first-party data like an email or phone, so Google can match a conversion to an ad click more reliably when cookies are missing. It is an add-on to your existing tag, not a replacement, and must follow your consent and privacy rules.
Google describes two versions. Enhanced conversions for web improves measurement of conversions that happen on your site, such as an online purchase. Enhanced conversions for leads improves measurement of offline sales that began as a website lead, such as an enquiry for an apartment that closes weeks later. Google hashes the data with SHA256 before it is used, and matches it against signed-in Google accounts that engaged with your ad.
What it is not: a way to track people who have declined consent, or a licence to collect more personal data than you told visitors about. Check what your privacy notice and the data rules in each market you sell in allow, and take proper advice if unsure.
When ad blockers and browser limits still drop too many events, the next step is server-side tracking: a server container in Google Tag Manager that sits between your site and the ad platforms. Google documents it under server-side tagging. This is the territory of our GTM engineering and tracking team, and worth it once spend is meaningful.
Track calls, WhatsApp taps and offline sales
Local businesses win or lose on calls and WhatsApp. Track clicks on tel and WhatsApp links as events, import calls from ads as conversions, and upload qualified or closed leads from your CRM so Google learns which clicks became customers, not only which became enquiries.
Cover the enquiries a form never sees
Tap events
In Tag Manager, fire an event when someone clicks a
tel:link or a WhatsApp link (wa.me). Mark it a key event only if it signals a real enquiry, and consider keeping it secondary.Calls from the ad
For calls placed straight from your ad, use call assets and call conversions in Google Ads, with a minimum call length so a wrong number does not count.
Capture the click ID
Store the GCLID in a hidden form field, with your UTM parameters, so it travels into your CRM next to the lead.
Upload the outcome
When a lead becomes a paying customer, import that sale back into Google Ads as an offline conversion. Google then learns which clicks produced revenue.
Why this beats optimising for form fills: a form fill is cheap to produce, and cheap leads are often poor ones. A bidding system that learns from closed customers steers toward the clicks that look like them. If your enquiries mostly arrive on WhatsApp, read our guide to setting up WhatsApp for leads so those chats carry a source too.
The 15-minute check before you scale spend
Pull last week's conversions from Google Ads, GA4 and your own enquiry sheet or CRM. They will not be identical, but they should tell the same story. If the CRM shows far fewer than Ads reports, you are counting something that is not a customer. Fix tracking before you raise the budget.
Put three numbers side by side for the same week:
| Source | Question it answers | Typical problem if high |
|---|---|---|
| Google Ads | Which clicks did Google credit? | Double tag, secondary actions counted |
| GA4 | How many key events fired? | Reloads, test submissions, bots |
| Your CRM or sheet | How many real enquiries arrived? | None. This is the reference. |
Walk any gap backwards. If Ads is above GA4, look for a second tag. If GA4 is above the CRM, look for thank-you page reloads, internal test submissions and spam. If all three are far apart, stop and fix tracking before judging campaigns. Only when they roughly agree should you compare conversion rate and cost per acquisition between campaigns.
Weekly reconciliation
With clean numbers you can decide where the next unit of budget goes. For that choice, see Google Ads vs Meta ads. If you would rather have it built and checked for you, our Google Ads management work starts with tracking, as part of our performance marketing practice.
Questions people ask
Either works; the rule is to count each action once. Google says you can use both together, but if both count the same form fill as a conversion, you will see it twice. Importing from GA4 suits businesses that want one place defining events. A native tag suits ads-only setups. Choose one per action.
They are the same idea under a new name. Google renamed GA4 conversions as key events in 2024, so GA4 now flags an important action as a key event. The word conversion now mostly lives in Google Ads, where an imported key event becomes a conversion action that can drive bidding and reporting.
The two systems credit differently. Google Ads credits the ad click and dates the conversion to that click; GA4 credits the session's source and dates it to when the event happened. Add double tagging, a reloaded thank-you page or test submissions, and Ads reads higher. Check your CRM to see which is closer to real customers.
Send a GA4 event whenever someone taps a tel: or WhatsApp link, using Google Tag Manager, and mark it a key event if it signals a real enquiry. For calls placed straight from the ad, use Google Ads call assets and call conversions. Then upload closed sales from your CRM so Google learns which enquiries paid.
Enhanced conversions send hashed first-party details, such as an email address, with your conversion so Google can match it to an ad click more reliably. They supplement your existing tag rather than replace it. They help when cookies are missing, particularly for lead businesses, but must follow your consent and privacy obligations.
Sources and further reading
- 1About key eventsAnalytics Help ·
- 2Create or modify key eventsAnalytics Help ·
- 3Connect Google Ads to Google AnalyticsAnalytics Help ·
- 4Create conversions from Google Analytics events in Google AdsGoogle Ads Help ·
- 5About enhanced conversionsGoogle Ads Help ·
- 6About conversion measurementGoogle Ads Help ·
- 7Google Tag Manager: server-sideGoogle for Developers ·
- 8Key events vs. conversionsAnalytics Help ·
- 9About phone call conversion trackingGoogle Ads Help ·
How we wrote this. Steps were checked against Google's Analytics Help and Google Ads Help pages fetched on 1 November 2026. Menu names change often, so each step names the destination and links the help page.
