An ecommerce Google Ads budget should be built around product economics, not a percentage of revenue or an “average” ROAS. The same media spend can be profitable for one category and destructive for another.
Start with allowable acquisition cost
Use gross margin, average order value, refund rate, repeat purchase behaviour and the proportion of new customers to decide what a first order can support. Then compare campaign performance with that limit.
Use current campaign inputs
Estimate traffic from current CPC or shopping-auction data and your own landing-page conversion rate. Segment products by margin, stock depth and strategic priority. Do not let a blended campaign hide which SKUs are consuming spend.
- Keep product feeds accurate.
- Separate prospecting from branded/existing demand where reporting needs it.
- Track purchases, refunds and customer type.
- Use search-term and product-level data to remove waste.
- Scale only when additional spend still creates acceptable contribution.
For the wider framework, see the 90-day ecommerce marketing plan.
