This is the cleaner, more controlled method of what you have asked,
Before You Start (Important Preparation):
Define Your Categories: Be crystal clear on which specific products/SKUs belong to which new category-specific PMax campaign. Use your Google Merchant Center feed attributes like product_type, google_product_category, or even custom_labels (if you've set them up for segmentation) to define these groups.
Budget Allocation: Decide how much budget you want to dedicate to each new category PMax.
ROAS Targets: Think about if each category truly needs a different Target ROAS. This is one of the main reasons to split.
Conversion Volume Check: Ensure each new category PMax campaign will likely get at least 15-20 conversions per month to enable its Smart Bidding (tROAS) to learn effectively. If a category is too small, it might be better to keep it grouped with others or manage it via Asset Groups in a larger PMax.
Step-by-Step "Whole Category Split"
Step 1: Create Your New, Category-Specific PMax Campaigns
Go to Google Ads: In your Google Ads account, click on "Campaigns" in the left-hand menu, then the blue plus button (+ New Campaign).
Choose Your Goal: Select "Sales" (or "Leads" if that's more appropriate).
Select Conversion Goals: Make sure the conversion actions relevant to sales (e.g., "Purchases") are selected for this new campaign.
Choose Campaign Type: Select "Performance Max."
Select Merchant Center & Country: Link your Merchant Center account and select the correct country feed (e.g., Australia).
Name Your Campaign Clearly: Give it a descriptive name, like "PMax - [Category Name] - AU" (e.g., "PMax - Luxury Gifts - AU").
Set Budget & Bidding: Set your daily budget and choose your bidding strategy (e.g., "Maximize Conversion Value" with your specific tROAS target for this category).
Targeting (Location & Language): Set your location (e.g., Australia) and language.
Crucial: Define Product Groups for THIS Category:
Go to "Listing groups" within your new PMax campaign's setup.
Click "Add subdivision" or the pencil icon next to "All products".
Subdivide by the attribute that defines your category (e.g., "Product type," "Google product category," or a "Custom label").
Select ONLY the products/SKUs belonging to this specific category. Ensure only these products are included. All other product groups should be excluded or not selected here.
Build Out Asset Groups: Create compelling Asset Groups for this category. Include high-quality images, videos, headlines, descriptions, and strong Audience Signals tailored specifically to this category's target audience.
Repeat Step 1 for each major category you want to split out into its own PMax campaign.
Step 2: EXCLUDE These Categories from Your Original "All Products" PMax Campaign
This is the most critical step to prevent overlap and competition!
Go to Your Original PMax Campaign: In your Google Ads account, navigate to your existing "all products" PMax campaign.
Go to "Listing groups": Within this campaign, find the "Listing groups" section (it's usually under "Asset Groups" or directly visible).
Identify and EXCLUDE the Migrated Categories:
You'll likely see "All products" subdivided, or a single "All products" group.
You need to exclude the product groups that correspond to the categories you just moved into their own new PMax campaigns.
For example, if you moved "Luxury Gifts" to a new PMax, find the "Luxury Gifts" product group in your old PMax's listing groups and set its status to "Excluded."
Ensure no product is actively targeted by more than one PMax campaign. This is the golden rule.
Step 3: Monitor and Optimize
Expect Learning Phases: Both your new category PMax campaigns and your original PMax (now running with a reduced product set) will enter a learning phase. Expect some fluctuations in performance for the first 2-4 weeks.
Monitor Closely: Keep a very close eye on performance:
New PMax Campaigns: Are they spending their budget? Are they hitting their tROAS targets? Are the conversions coming in?
Original PMax Campaign: How is its ROAS and volume doing with the reduced product set?
Adjust as Needed: Be ready to fine-tune budgets, tROAS targets, and asset groups based on early performance data.
This structured approach ensures you gain the control you're looking for without creating messy internal competition. Good luck!
