Optimising a PMax Campaign
I recently set up a PMax campaign for our website which is split into asset groups by the product type. We currently have 4 products in 2 colour ways and then we’ve created bundles of the products. So I have set up 5 asset groups – 1 for each product type and then 1 for the bundle products.
I have set the campaign to ‘Maximise Conversions’ and left the Target CPA open to collect data. However, this is getting through £60-£100/day and returning a few conversions but not enough to cover the expenditure. I understand that the campaign needs to build up data by getting traffic and conversions, but I would like to start at least making the campaign break even with the view to making profitable as soon as possible.
Are there any tips on target audience, audience signals, search themes etc to target ready to buy customers more easily so that I can start returning a profit on Google Ads? Thanks.
The short answer is:
Your problem is typical for an under-optimized PMax campaign that’s wasting budget on non-converting traffic because it’s optimizing for the low-quality default ‘Conversions’ instead of ‘Conversion Value’ plus a minimum return.
You need to switch your bidding strategy to Maximize Conversion Value with a Target ROAS (tROAS) immediately, set that tROAS to your break-even point or slightly higher, and provide high-quality audience signals like your past purchasers and cart abandoners.
Simultaneously, you should audit your conversion tracking to ensure you are accurately reporting the dollar value of each product and bundle purchase using a robust server-side setup like Google Ads API and Google Tag Manager with a service like Stape or Google Cloud Platform to prevent data loss and give the AI the clearest signal possible.
The long answer is:
The fact that you are getting conversions but not enough to cover the expenditure suggests two things: first, your conversion tracking is likely only reporting the binary action (a conversion happened) and not the value of the purchase, and second, your bidding strategy is pushing Google’s AI to find the cheapest conversion regardless of the revenue it generates.
To correct this, you must change your bidding strategy and dramatically improve your data quality.
First, you need to switch from Maximize Conversions to Maximize Conversion Value.
Since you want to break even as soon as possible, you must set an initial Target ROAS (tROAS).
Calculate your break-even ROAS (1 / profit margin) or a slightly higher, conservative number, and enter that as your tROAS.
This tells Google’s AI, “Only bid on auctions where the expected return is this high,” which directly steers your campaign toward profitability.
For a new campaign, you might start with a tROAS that’s just below your actual break-even to ensure adequate volume, then increase it every few weeks as the performance improves.
Second, your asset groups are correctly split by product type, but you need to feed the AI much stronger guidance through Audience Signals.
Since you are looking for ready-to-buy customers, your most powerful signals will be custom audiences based on your first-party data.
These should include Customer Match lists of past purchasers, particularly high-value ones, and website audience lists of users who viewed a product or abandoned a cart but have not yet purchased.
You should also create an ‘In-Market’ or ‘Custom Segment’ list of people actively searching for your product or very similar products.
Uploading these lists will help the AI find new users that look like your most valuable existing customers, accelerating the learning phase and focusing your spend on high-intent users.
Also, review your product titles in Google Merchant Center to ensure they are rich in keywords that ready-to-buy customers would use, like “red wool scarf bundle gift set” instead of just “bundle.”
Third, and perhaps most critical in the long term, you must ensure your reported conversion value is completely accurate and reliable.
This is where using the Google Ads API, Google Tag Manager, and a server-side solution like Stape or Google Cloud Platform becomes an excellent and cheap solution.
Standard browser-side tracking using just Google Tag Manager’s web container is subject to severe data loss due to ad-blockers, ITP, and other privacy restrictions, which can sometimes block up to 30% of your data.
This means Google’s AI is making bidding decisions with incomplete and inaccurate data, leading to poor performance.
By implementing server-side tracking, you use the Google Tag Manager server container to send data to the Google Ads API from your own server (hosted affordably on Stape or Google Cloud Platform).
This bypasses browser restrictions, giving you nearly 100% data fidelity.
This ensures that every conversion and, crucially, the precise dollar value associated with each purchase (including product, color, and bundle) is accurately sent as a purchase Standard Event to Google Ads.
The Google Ads API is the channel you use to send this high-quality, server-side data directly to your Google Ads account, which provides the AI with the complete picture it needs to hit your ambitious Target ROAS and make your PMax campaign profitable.
The initial setup requires technical skill, but the hosting costs on a service like Stape are very low compared to the $60-£100/day you are currently losing to poor optimization.
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