Tracking Purchases Only
Many merchants only track purchases, ignoring the rest of the funnel. This gives Google's AI incomplete data to optimize against.
- • Add to Cart signals
- • Checkout initiation data
- • High-intent user behavior
- • Track Add to Cart (secondary)
- • Track Begin Checkout (secondary)
- • Keep Purchase as primary
Why it matters: Full-funnel tracking gives Smart Bidding more signals to identify high-value users earlier in their journey.
Not Using Enhanced Conversions
With privacy restrictions growing, relying only on cookies means you're missing 20-40% of your conversions.
The Privacy Problem
Safari blocks tracking after 7 days. iOS limits data. Ad blockers prevent tags from firing. Without Enhanced Conversions, you're flying blind on a significant portion of your traffic.
The Fix: Enable Enhanced Conversions to use first-party customer data for better matching.
Learn how to set up Enhanced ConversionsDuplicate Conversion Tags
This happens when you have multiple tracking methods active: GTM setup, native Shopify integration, AND a third-party app all firing at once.
- • Inflated conversion counts
- • Artificially low CPA
- • Bad optimization decisions
- • Wasted budget
- • Audit all active tracking
- • Choose ONE primary method
- • Remove or disable others
- • Use Tag Assistant to verify
Wrong Conversion Value
If your conversion value doesn't match reality, your ROAS calculations are meaningless.
Common Value Mistakes:
- Including tax in some transactions but not others
- Currency mismatches between Shopify and Google Ads
- Including or excluding shipping inconsistently
- Using fixed values instead of dynamic order totals
The Fix: Standardize on product subtotal (excluding tax and shipping) for consistent ROAS comparison.
Ignoring Attribution Settings
Google Ads now defaults to data-driven attribution, which distributes credit across touchpoints. If you're expecting last-click numbers, you'll be confused.
Understanding Data-Driven Attribution
A single conversion might show as 0.4 conversions on one campaign and 0.6 on another. This isn't an error. It's credit distribution. Total conversions remain accurate.
The Fix: Understand your attribution model and align your expectations. Use the Model Comparison tool in Google Ads to see differences.
Not Testing After Shopify Updates
Shopify regularly updates their checkout, themes, and APIs. Each update can potentially break your tracking.
Recent Breaking Changes:
- Checkout Extensibility migration changing thank-you page behavior
- Theme updates affecting script loading
- Web Pixel API changes
The Fix: Test your tracking with a real purchase after every major Shopify update. Set calendar reminders for monthly audits.
Relying on Client-Side Only
Client-side tracking (browser-based) is increasingly unreliable. Ad blockers, privacy browsers, and iOS restrictions all prevent tags from firing.
The Reality
Up to 40% of users may have some form of tracking prevention enabled. That's 40% of your conversions at risk.
The Fix: Supplement client-side tracking with Enhanced Conversions or server-side tracking where possible.
How to Audit Your Current Setup
Use this checklist to identify issues in your tracking:
- Compare Shopify orders to Google Ads conversions (allow 3-day lag)
- Check for duplicate tags with Google Tag Assistant
- Verify conversion values match Shopify order totals
- Confirm Enhanced Conversions is enabled and recording
- Test a real purchase and verify it appears in Google Ads
- Review attribution model and understand credit distribution
Stop Making These Mistakes
ScaleUp prevents all 7 mistakes: full-funnel tracking, Enhanced Conversions, deduplication, correct values, and automatic updates.
Install Free on ShopifyNo credit card required
Sources & References
About the Author
Jamie Scott
Founder & CEO, ScaleUp
Jamie specializes in e-commerce conversion tracking, helping Shopify merchants improve their Google Ads performance.