# Amazon seller benchmarks: real ACoS & Buy Box data

URL: https://aiadking.com/data/amazon-seller-benchmarks
Updated: 2026-09-03

Real benchmarks from live Amazon seller accounts: median ACoS, wasted ad-spend share, Buy Box loss rate. Actual account data, not surveys.

Amazon seller benchmarks (AIAdKing platform aggregates). Anonymized aggregate metrics from live Amazon seller accounts: median ACoS, wasted ad-spend share, Buy Box loss rate, aged and stranded FBA stock, review-request volume.

## Key figures

- Median 30-day ACoS: 52.5% (Median settled ACoS across seller accounts with meaningful ad sales (10 accounts; windows end 7 days back so Amazon's late attribution doesn't inflate the number). Range: 24% to 111%. Most portfolios run far hotter than the "25-30%" survey averages quoted around the web.)
- Ad spend on proven-waster search terms: 10.8% (Share of the last 30 days' search-term spend sitting on terms with 15+ clicks and zero attributed orders — enough evidence to call them wasters. Roughly one dollar in nine buys clicks that have already proven they don't convert.)
- Ad spend on zero-order terms (raw): 39.9% (Same window, all search terms with zero attributed orders regardless of click count. The gap between this raw figure and the 10.8% proven share is why negating on thin data destroys campaigns: most zero-order terms just haven't had enough clicks to judge.)
- Buy Box checks lost: 11.7% (Across 14,762 hourly Buy-Box checks in the last 30 days, sellers did not hold the box in 11.7% of checks — one in nine buyer visits landing on someone else's offer.)
- Stocked FBA products currently stranded (platform-wide): 2 in 3 (Right now, 104 of 152 products holding FBA units on the platform cannot sell due to listing problems — heavily driven by a few accounts with bulk listing errors, which is exactly how stranding happens in the wild: not evenly, but in silent batches.)
- FBA units older than 180 days: 4.5% (Of 9,783 FBA units tracked, 4.5% sit in the 181+ day age buckets — the window where Amazon's long-term storage surcharge is either imminent (181-270 days) or already billing (271+).)
- Compliant review requests sent (30 days): 1,899 (Official Amazon Request-a-Review messages sent automatically for eligible orders in the last 30 days — one per order, Amazon's own wording, inside the 5-30 day window.)