Google Ads
When Should You Split Products Into Multiple PMax Campaigns?
Split PMax campaigns when separate control creates a business advantage. Do not split them merely because the product catalogue has neat categories.
Good reasons to separate
Different target ROAS or CPA; drastically different margins; separate countries; seasonal products; inventory constraints; hero products that deserve dedicated budget; new products requiring controlled testing.
Weak reasons to separate
"Shoes and hats are different categories" is not enough if both have similar economics and target the same market. Fragmentation can reduce conversion data and create more moving parts without improving results.
Ask what decision the split enables
A separate campaign should let you do something useful: allocate budget, set a different target, isolate a market or protect a priority product group. If the answer is simply "better organization," consider using listing groups, feed labels or reporting dimensions instead.
Measure after the split
Watch total Google performance, not only whether each new campaign gets a prettier ROAS. Redistribution of attribution between campaigns can look like improvement without creating more Shopify revenue.
Need this checked against your own numbers?
If your PMax structure has become too consolidated or too fragmented, contact us. We can group products around the differences that actually affect advertising economics.