Reviews on the PDP — placement, Vine, sort.

Reviews are the most-read text on the entire PDP. Internal Amazon studies (and every external one) put the review block at the top of the trust hierarchy — above bullets, above A+, above brand. Treat it as a first-class element of the listing, not a passive output.

Where reviews render

• Star rating — top of the page, next to the title.
• Top-reviews snippet — sometimes pulled high on mobile.
• Full review block — below A+ on desktop, accessed via tap on mobile.
• "Customers say" AI summary — Amazon's machine-generated digest, rolling out by category.

The filter UI that changes what shoppers see

The sort and filter controls let shoppers narrow by star count, by image-only, by verified-purchase, and by topic. The default is "Top Reviews" (algorithmic), which surfaces the reviews Amazon thinks are most helpful — not the most recent. That gives the top three or four reviews a long half-life. A well-written 5-star early review can carry a listing for years.

Rating thresholds that gate visibility

• 4.0 stars — disqualifies from the "4 stars & up" filter on the SERP.
• 4.5 stars — qualifies for Amazon's Choice in most categories (combined with other signals).
• 15 reviews — minimum threshold for the star block to render with a count rather than as "no reviews yet" on some surfaces.

Vine

Amazon Vine seeds early reviews from trusted reviewers in exchange for the product. Use it on new ASINs to break the cold-start problem — but expect Vine reviewers to be more critical than organic, so launch with a polished product, not a beta.

What you can't do

Incentivising reviews (including review-for-discount and review-clubs) is a hard TOS violation. The only compliant levers are: Request-a-Review (one-click, 5–30 days post-delivery), Vine, and product/listing quality.