How to Set Up GA4 Conversion Tracking for Leads, Calls, and Sales

GA4 conversion tracking records the leads and sales your marketing produces as key events you can report on in Google Analytics and send to Google Ads for bidding. Since March 2024, Google Analytics 4 (GA4) calls these actions key events, while the word “conversion” now refers to the version used inside Google Ads. Getting this right matters: if your tracking counts the wrong actions, double-counts form submissions, or never reaches Google Ads, your reports and your ad bidding both work from bad data. This guide shows how to choose your key events, set them up step by step, track forms, calls, and purchases with Google Tag Manager (GTM), import them into Google Ads, and understand why the two platforms rarely report identical numbers.

Key Takeaways

• In GA4, important actions are called key events. When you create a Google Ads conversion from a key event, it becomes a conversion there.
• Key events don’t become Google Ads conversions on their own. You must link the accounts, create a conversion from each key event, and confirm it’s set as primary if you want bidding to use it.
• Track form leads with a confirmed success signal, such as a thank-you page or a data layer event, rather than relying only on GA4’s automatic form events.
• GA4 and Google Ads numbers differ by design. Google Ads credits the click date, while GA4 records the event date, and the two also use different attribution rules and counting settings.
• Test every key event in GTM Preview and GA4 DebugView before you rely on the data.

What Is a Key Event in GA4?

A key event is any GA4 event you mark as important to your business, such as a lead form submission, a booked call, or a purchase. GA4 collects everything as events. Marking one as a key event tells GA4 to count it in key event reports and attribution. Google Ads can then use that key event as the basis for a conversion.

Plan Your Key Events Before You Build

Track the actions that represent real business value, and keep the list short. According to Google, a standard GA4 property can mark up to 30 events as key events (50 for Analytics 360). Too many key events dilute reports and confuse bidding anyway.

Use GA4’s recommended event names where they fit, such as generate_lead and purchase. Recommended names keep your data consistent and make standard reports work as expected. For custom events, use lowercase names with underscores, such as demo_request. Event names are case-sensitive.

How to Set Up a Key Event in GA4 (Step by Step)

1. Choose the action. Pick one specific outcome, such as a successful contact form submission, and name the event (for example, generate_lead).
2. Send the event to GA4. Create a GA4 Event tag in Google Tag Manager that fires on the action’s success trigger, or use an event GA4 already collects.
3. Test it. Use GTM Preview mode and GA4’s DebugView to confirm the event fires once, at the right moment, with the right parameters.
4. Mark it as a key event. Follow Google’s key event instructions:
   • If GA4 has already received the event, go to Admin > Data display > Events and mark it as a key event. Depending on your interface, this is a Mark as key event toggle or a star icon.
   • If the event hasn’t arrived yet, go to Admin > Data display > Key events, select New key event, and enter the exact event name.
   • You need at least Editor access to mark an existing event, and Marketer access to create a new key event.
5. Check the counting method. “Once per event” is the default for most key events. Key events created from Universal Analytics goals, either in an automatically created GA4 property or with the goals migration tool after April 2023, default to “Once per session.” You can change the method under Admin > Data display > Key events. “Once per session” can help prevent duplicate lead form submissions from inflating your numbers.
6. Add a value. Assign a default value or pass a dynamic value from your data layer, so GA4 can report lead and revenue value. Send values as numbers, or Google Ads won’t be able to use them.
7. Create a Google Ads conversion if you run ads, as covered below.

Marking an event as a key event affects reports from that point forward and doesn’t change historical data. Per Google’s counting method guidance, counting method changes also apply only to future key events. Google says new key events can take up to 24 hours to appear in standard reports. Realtime and DebugView update much sooner.

Track Form Leads Reliably With Google Tag Manager

GA4’s enhanced measurement can record form interactions automatically, but those events don’t always mean a lead actually arrived. They can be inconsistent across form tools and don’t confirm that the submission succeeded. For leads you’ll report on or bid against, use a confirmed success signal.

Example GTM setup for a data layer event:

• Trigger: Custom Event, event name form_success
• Tag: GA4 Event, event name generate_lead, with parameters such as form_name and value
• Key event: mark generate_lead in GA4

Track lead quality beyond the form. A form fill isn’t a customer. Pass CRM stages, such as qualified lead or closed deal, back into your analytics and ad platforms so you can optimize toward revenue. Automated workflows that connect your CRM and analytics make this repeatable; see our automation setup service. For a SaaS-specific view of lifecycle data, read our guide to marketing automation for SaaS.

Track Phone Calls

Calls are often the highest-value leads for service businesses, and they’re easy to miscount.

Track phone link clicks as a supporting event. Use real call data, ideally with a minimum call duration, as your key event or Google Ads conversion.

Track Ecommerce Sales

For online stores, send the GA4 purchase event with these parameters:

• transaction_id
• value
• currency
• items

GA4 marks purchase as a key event by default. A unique transaction ID helps you spot duplicates, which often happen when shoppers reload the order confirmation page. Most ecommerce platforms offer a native GA4 integration or app. Use one integration only, because running both a platform app and a manual GTM purchase tag is a common cause of double-counted revenue.

Import GA4 Key Events Into Google Ads

Key events don’t flow into Google Ads on their own. Start by linking the accounts in GA4 under Admin > Product links > Google Ads links. Then create the conversion from either side, following Google’s import instructions.

Create the Conversion in Google Ads

1. In Google Ads, click the Goals icon, then open the Conversions menu.
2. Click New conversion action, then select Import.
3. Choose Google Analytics properties, then Web, and click Continue.
4. Select the key events you want, then click Import and continue, then Done.

Or Create It From GA4

In GA4, go to Advertising, then under Tools, select Conversion management and click New conversion. Choose the Google Ads account and the key events to share. Google notes that conversions created this way are set as secondary, so they won’t drive bidding until you change them in Google Ads.

Review the Settings in Google Ads

• Action optimization (primary vs. secondary). Only primary actions count in the Conversions column and drive Smart Bidding. Imported actions can default to either, depending on how they were created and your account history, so check each one.
• Count. Google recommends Every for sales and One for leads.
• No historical backfill. Google’s documentation notes that imported data starts from the day you import, not before.
• One primary source per action. Don’t set both a GA4 import and a Google Ads tag conversion for the same action as primary, or bidding will count it twice.

GA4 import or the Google Ads tag? Both work. Many advertisers use the Google Ads tag, with enhanced conversions, for bidding-critical actions and GA4 imports for cross-channel reporting. Pick one primary source per action and document it. If you’d rather have your account structure and bidding handled for you, our Google Ads management team sets this up as part of onboarding.

Why GA4 and Google Ads Conversions Don’t Match

Different numbers usually mean different rules, not broken tracking.

How to compare fairly: match the date range, use the same counting method, and compare a specific campaign rather than account totals. For Google Ads, also check the “conversions by conversion time” column. Expect some difference even then.

Consent Mode, Enhanced Conversions, and Server-Side Tracking

• Consent mode passes each visitor’s consent choices to Google tags, which adjust their behavior to match. According to Google’s consent mode documentation, parameters such as ad_user_data and ad_personalization control whether user data can be sent for advertising and used for personalization. Consent mode is required to keep certain measurement and personalization features for European Economic Area visitors, and it lets Google model some conversions it can’t observe directly.
• Enhanced conversions send hashed first-party data, such as an email address from a form, alongside a conversion so Google Ads can match conversions it would otherwise miss. When a visitor denies ad_user_data consent, that hashed data isn’t used, so consent mode and enhanced conversions need to be set up together.
• Server-side tagging routes tracking data through a tagging server you control before it reaches Google and other platforms. It gives you more control over what data is shared and can improve data quality. It does not override consent or make tracking exempt from privacy rules.

Start with solid client-side tracking and consent mode. Add enhanced conversions next. Consider server-side tagging once your volume and data requirements justify the extra setup and hosting cost.

Test and Troubleshoot Your Setup

Enable debug mode through GTM Preview or Google Tag Assistant, then open Admin > Data display > DebugView in GA4 to watch events arrive in real time, as described in Google’s DebugView guide. If you use consent mode and decline analytics cookies while testing, your events won’t appear in DebugView, so accept them on your test device.

Get Your Tracking Audited

If your lead counts don’t match your CRM, or Google Ads is bidding on clicks that never become customers, the problem is usually in the setup, not the ads. Seattle PPC’s analytics and tracking setup service configures GA4, Google Tag Manager, call tracking, and Google Ads conversions so every key event is counted once and tied to revenue. Book a tracking audit to find out what your current setup is missing.

Disclaimer: GA4 tracking features, settings, and Google Ads integrations may change over time. Implementation requirements can vary depending on your website, tag configuration, and consent setup. Always verify your tracking setup with Google’s latest documentation and test events before relying on the data for reporting or advertising decisions.