You're seeing high impression share but low impressions because you're dominating a small slice of the market, not the full available demand.
- Your campaign is eligible for only a narrow range of searches—maybe due to limited keywords from your product feed (titles/descriptions), low bids, or restrictive settings.
- Google is saying: “Out of the few auctions you qualify for, you're showing up most of the time”—which gives you a 63–66% impression share.
- But since the total eligible volume is small, your actual impressions and spend stay low.
What to Do:
- Optimize your product titles and descriptions to match more popular search terms.
- Ensure your product feed is clean and approved in the Merchant Center.
- Review campaign settings—expand location, audience signals, or device options.
- Consider loosening your ROAS targets or increasing your max CPC if using Manual or tROAS bidding.
You're winning most of a limited auction pool. To grow impressions and spend, you need to expand your eligibility—not just increase budget.