In today’s AI-powered advertising ecosystem, setting up a Google Ads campaign is no longer just about keywords, ad copy, or even audiences—it’s about data. Specifically, the conversion data you feed to Google’s machine learning system. That’s why understanding the distinction between primary and secondary conversion actions, and optimizing your campaigns for the right one, is more important than ever.

Failing to set this up properly can derail your performance, burn through budget, and leave automation optimizing for the wrong outcome. Let’s explore how to get this right.

Primary vs. Secondary Conversions: What’s the Difference?

In Google Ads, primary conversions are the actions you tell Google to optimize for. These are the conversions that Smart Bidding strategies use to learn and adjust. They also appear in your standard “Conversions” column.

Secondary conversions, on the other hand, are tracked but not used for optimization. These show up in the “All Conversions” column, providing valuable insight into other user behaviors that matter to your business but aren’t the core KPI for campaign performance.

Examples:

  • Primary Conversion: Completed purchase, qualified lead form submission, phone call over 60 seconds
  • Secondary Conversion: Newsletter signup, add-to-cart, page scroll depth, live chat engagement

By clearly defining these, you’re not just organizing your reporting—you’re telling Google’s algorithm which signals to prioritize.

Why Your Optimization Conversion Matters

When using Smart Bidding strategies like Target CPA, Maximize Conversions, or Target ROAS, Google’s algorithms need a “North Star”—a specific conversion action to guide bidding decisions. If your campaign is optimizing toward a secondary or less-valuable action (like a page view or low-intent form fill), the algorithm will drive more of that behavior—even if it doesn’t equate to real revenue.

This can create misleading performance and lower your actual return on ad spend (ROAS), even if your conversion numbers look “good” on the surface.

The Risks of Including Too Many Conversions in Optimization

It’s tempting to track every micro-conversion and consider them all valuable. But not all conversions should be optimized for. If you mark everything as a primary action—newsletter signups, contact form views, eBook downloads—Google will treat all of them with equal importance.

This dilutes campaign focus and confuses the algorithm, which results in inefficient bidding and wasted budget on lower-value actions.

Instead, prioritize one (or a small few) high-intent, bottom-funnel actions as your primary conversions and keep other useful actions labeled as secondary for analysis only.

How This Impacts Reporting and Strategy

When you set up conversion actions correctly:

  • “Conversions” column reflects only your primary KPIs
  • “All Conversions” column gives broader behavioral insight
  • You can segment and evaluate campaigns more accurately
  • You gain cleaner data for A/B testing and performance modeling

This allows you to better analyze true business impact, rather than just volume of actions taken.

Smarter Conversion Strategy, Smarter Campaigns

Clearly distinguishing between primary and secondary conversions ensures that your campaigns are optimized for the actions that truly move the needle for your business. It’s no longer enough to just track conversions—you must actively curate which ones to optimize for.

Because when you teach the algorithm to chase the right outcomes, that’s when Google Ads becomes a growth engine—not just an ad platform.