Google Ads Conversion Actions: Primary, Secondary and What to Count

Google Ads optimises towards what you tell it counts as a conversion. If you tell it that a page view counts, it will find you page views. If you tell it that a purchase counts, but count the same purchase twice, it will learn from numbers that are not real. The setup of conversion actions is therefore not a technical detail. It decides what the account is trying to achieve.

This guide explains the choices that matter for a store, and the mistakes that cause trouble.

What a conversion action is

A conversion action is a defined event that you want to count, such as a purchase, a lead form or a booked call. Each action has its own source, its own counting rule and its own value. Google Ads uses them for reporting and, depending on the settings, for bidding.

Primary and secondary actions

Not every action should steer the bidding.

Primary

What it does: Included in the main conversions column and used for bidding

Typical use: The action that matters most, such as a completed purchase

Secondary

What it does: Observed for reporting, not used to steer bidding

Typical use: Supporting steps, such as add to cart or a page of interest

Keep the primary list short. Too many primary actions blur what the system optimises towards.

The usual mistake is to mark every step of the funnel as primary. The bidding then rewards cheap, early actions instead of purchases.

What to count

• Purchases: count every purchase, because each one is a real sale, and send its value and currency.
• Leads: for a form or call, count one conversion per person, because several submissions from the same visit are not several customers.
• Lower-value steps: make them secondary so you can see them without steering the account.

Values must be real

If the account is optimised for value, the value you send must be right. A wrong or missing value teaches the wrong lesson. Send the order value and a valid currency, and check that discounts and taxes are handled in the way you decided.

Avoid counting the same sale twice

This is the most common serious problem. A store may count a purchase through a Google Ads tag and also import a purchase from GA4. If both are primary, the same sale can be counted twice.

1. 1

   List every source

   Google Ads tag, GA4 import and any other

   Know what exists before changing anything
2. 2

   Choose one primary source for purchases

   Keep the other as secondary or remove it

   One sale, one count
3. 3

   Check the transaction ID

   The same order must carry the same ID

   This helps the system recognise repeats
4. 4

   Compare with your store

   Orders in the store against conversions in Google

   Explain the difference, do not ignore it

The broader topic of mismatched numbers is in Why Your Store Sales Don't Match Meta and Google Ads. For the same problem on the Meta side, see Duplicate Purchase Events: Causes and How Deduplication Works.

Customer data and consent

To improve matching, Google offers a feature that uses hashed customer details you already hold, often called enhanced conversions. Use it only with data you legitimately have, and respect the consent choices of your audience and the rules where you operate. Check Google's current documentation for the exact setup.

Cash on delivery

If you sell with cash on delivery, an order placed is not yet a kept sale. Decide whether the primary action is the order placed or a later, stronger signal, and be consistent. The cost of the gap between the two is explained in How to Calculate Your Advertising Break-Even Point Before Scaling, and the Delivery Signal service exists for sending a later signal.

A short checklist

1. One primary source for each important action.
2. Purchases carry a real value and currency.
3. Lower-value steps are secondary.
4. No sale is counted by two sources.
5. Conversions are compared with store orders, and the difference is understood.

If you want the setup reviewed or built, the tracking setup service covers it, and the audit finds duplicates in an account you already run. For choosing between Search and Shopping, see Google Search vs Shopping Ads for an E-commerce Store.