Changing your bid strategy from Manual CPC (which focuses on clicks and requires you to set the maximum bid) to Target CPA (Cost Per Acquisition, an automated strategy that focuses on conversions) is a significant step towards using Google’s machine learning to meet your business goals.

Here is a step-by-step guide and the important requirements for this switch.

Phase 1: Pre-Switch Requirements (Crucial First Steps)

Before switching to Target CPA, you must ensure the following are in place, as Target CPA relies entirely on this data:

1. Conversion Tracking is Active: Your Google Ads conversion tracking must be set up, working correctly, and measuring the action you want to optimise for (e.g., form submissions, calls, purchases). Without conversion data, Target CPA cannot work.

2. Sufficient Conversion Volume: Google recommends having a minimum of 15 conversions in the last 30 days in the campaign you are switching.

• Note: The more data you have, the better Target CPA will perform. If you have fewer than 15, the learning phase will be longer and less stable.

3. Define Your Target CPA: You need a realistic target to enter.

• Advise: Do not use your goal CPA initially. Instead, calculate your actual average CPA from the last 30 days of running on Manual CPC, and set the target about 10-15% higher than that number. This gives Google’s AI room to find volume and learn before you try to drive the cost down.

Phase 2: The Step-by-Step Change

Step 1: Navigate to Campaign Settings

1. Sign in to your Google Ads account.

2. In the left-hand menu, click Campaigns.

3. Click settings of the specific campaign you want to change.

Step 2: Access the Bidding Section

1. On the Settings page, scroll down to the Bidding section.

2. Click the link that says Change bid strategy.

Step 3: Select the New Strategy

1. In the ‘What do you want to focus on?’ section, select Conversions.

2. Underneath, you will see a dropdown labelled ‘Select a bid strategy’. Select Target CPA.

• Note: If you have enough conversion data, Google may automatically default to Maximize Conversions and give you the option to set a target CPA. Functionally, Maximize Conversions with a Target CPA is the new version of the older Target CPA strategy.

Step 4: Set the Target CPA Value

1. A field will appear asking you to Set a target cost per action.

2. Enter the target CPA value you calculated (e.g., £25.00).

Step 5: Save Your Changes

1. Click the blue Save button at the bottom of the Settings page.

Our Advice

1. The Learning Phase is Real

• Note: After you switch, the campaign will enter a “Learning” phase. For the first 7-14 days, you may see fluctuations in traffic, clicks, and conversion cost as the AI figures out which auctions are most likely to hit your target.

• Advise: Do not make any major changes during this time (e.g., pausing keywords, changing the budget, or adjusting the Target CPA). Let the machine learn.

2. Budget Matters More Now

• Advise: Ensure your campaign budget is high enough. Google recommends a daily budget that is at least 10-15 times your Target CPA.

• Example: If your Target CPA is £25, your daily budget should ideally be £250 to £375.

• If your budget is too low relative to your target, the campaign will be “Limited by budget” and the AI will struggle to find conversions efficiently.

3. Don’t Set a Max. CPC Cap

• Note: You can set a maximum CPC bid limit within the advanced settings for Target CPA, but this is strongly advised against.

• Opinion: The main power of Target CPA is that it can bid very high on a highly valuable search (e.g., someone searching for “emergency plumber near me”) and very low on a less valuable one. Setting a Max CPC cap prevents the AI from making those high, profitable bids and will severely limit your conversion volume.