Attribution
Blended ROAS
Total revenue divided by total ad spend across all channels. A top-level health metric that shows overall advertising efficiency but hides which channels are driving incremental value and which are free-riding. A brand with a 4x blended ROAS might have Meta at 6x and Google Display at 1.2x, but blended ROAS won't tell you that. Useful as a directional metric for month-over-month trending, but should never be used for channel-level budget allocation decisions.
Why it matters
It is the only ROAS figure that cannot be inflated by double-counting, because its denominator is total spend and its numerator is total revenue.
In practice
Track it as the primary number and platform ROAS as diagnostics beneath it. If blended is flat while every channel improves, the channels are trading credit, not creating revenue.
Related terms