Google Ads Conversion Tracking: Complete Setup Guide

Why Conversion Tracking Matters

Without accurate conversion tracking, you're optimising blind. You can't identify which keywords, ads, and audiences drive results. You can't use automated bidding effectively. And you have no way to calculate true ROI.

We regularly audit accounts where poor tracking is silently destroying performance—duplicate conversions inflating numbers, missing tracking letting winners look like losers, or wrong conversion actions optimising campaigns for the wrong goals.

Types of Conversions to Track

Primary Conversions

These are your main business goals and should be marked as "Include in Conversions" for bidding optimisation:

• Purchases (for e-commerce)
• Form submissions (for lead gen)
• Phone calls over 60 seconds
• Booked appointments

Secondary Conversions

Track these for insights but exclude from bidding:

• Email signups
• Content downloads
• Add to cart (without purchase)
• Page engagement signals

Implementation Methods

Google Tag (Recommended)

The Google tag (gtag.js) can be implemented directly or through Google Tag Manager. It provides the most reliable tracking and supports enhanced conversions.

Import from GA4

You can import conversion events from Google Analytics 4. This is useful for consistency but can have attribution differences. Use this as a secondary tracking method, not primary.

Enhanced Conversions

Enhanced conversions improve tracking accuracy by sending hashed first-party data (email, phone, name) alongside conversion events. This helps Google match conversions back to ad clicks even when cookies are blocked or users switch devices.

When to Use Enhanced Conversions

• Lead generation forms where you collect email
• E-commerce checkouts with customer details
• Any conversion with user-submitted information

Conversion Values

Always assign values to your conversions. This enables value-based bidding strategies (Maximise Conversion Value, Target ROAS) which typically outperform volume-based strategies.

• E-commerce: Use dynamic values (actual order amounts)
• Lead gen: Calculate average deal value × close rate
• Multiple actions: Assign relative values (demo = £100, whitepaper = £10)

Common Tracking Mistakes

• Duplicate tracking: Both gtag and GTM firing for the same event
• Wrong conversion window: Using 30-day click for products with 90-day sales cycles
• Missing conversion values: Preventing use of value-based bidding
• Tracking wrong page: Firing on form page instead of thank-you page
• No testing: Not verifying tracking works before launching campaigns

Auditing Your Tracking

• Use Google Tag Assistant to verify tag firing
• Check the Conversions page for status issues
• Compare GA4 and Google Ads conversion numbers
• Test a conversion yourself monthly
• Review attribution reports for anomalies