The recommended default bidding strategy for Sponsored Products campaigns outside of an aggressive launch push: 'Dynamic bids — down only.' Amazon is allowed to lower a bid below the set amount when a click looks unlikely to convert, but never raise it above the set bid. This is contrasted with fixed bids, which lock in a cost-per-click that doesn't adapt to Amazon's own real-time conversion-likelihood signal, and with 'dynamic up and down,' which lets Amazon raise bids above the set amount — reserved for the Aggressive Launch Bidding Strategy (Over-Bidding + Dynamic Up/Down) phase rather than steady-state management. Down-only is the safer, margin-protecting default once a listing is past launch.
Amazon's third bid-adjustment mode, alongside dynamic-down (the default) and dynamic up-and-down (see Aggressive Launch Bidding Strategy (Over-Bidding + Dynamic Up/Down) for the aggressive/launch use case), is Fixed — the bid is never adjusted by Amazon at auction time. Use fixed bids only when the exact correct bid is already known from historical performance; otherwise the dynamic modes let Amazon adjust for you.
'Up and down' bidding is used only temporarily on a new auto campaign if impressions aren't coming in at all — once a bid is found that generates impressions, the campaign is reverted back to 'down only' as the steady-state setting.
Default new auto campaigns to down only (Amazon may only lower your bid, never raise it). If an auto campaign isn't getting impressions, temporarily switch to up and down so Amazon can bid above your set amount to win auctions — once a working bid is found, lock it in and revert the campaign back to down only.
Chris Rawlings frames this as the safe default: "whenever you're in doubt, just go with down only." It's the baseline for most campaigns, especially multi-keyword, exact-match Performance campaigns built around a shared shopper-intent theme.
Amazon states the bid is lowered specifically when the ad is judged less likely to convert to a sale, or when competition for the placement drops — the ceiling itself never moves up under this strategy.
Rawlings offers a rough cross-strategy equivalence: a $6 down-only bid is economically similar to a $3 Dynamic Bids Up and Down (Amazon PPC Bidding Strategy) bid, since up-and-down can only double the entered amount. Useful when translating a starting bid between the two strategies.
In a 90-day, PPC-only product launch ($100K revenue, 14% average ACOS), 'dynamic bids – down only' was applied as the default bidding strategy across every campaign type — category targeting, semantic-grouped phrase match, brand defense, and automatic targeting — with placement modifiers deliberately withheld until enough performance data accumulated to set them meaningfully. See Placement Bid Adjustments (Top of Search / Rest of Search / Product Pages).
Used as the default bid strategy across category-targeting, Defense / "Shielding" Campaigns (Product Targeting), and Automatic Campaign Four-Way Split (Close Match, Loose Match, Substitutes, Complements) setups at launch, with no bid modifiers layered on top.
Down-only is the sensible default for phrase, broad, and exact match campaigns because the bid for each is already set individually per keyword — there's no need for Amazon to raise it further, only to pull back on placements or auctions that underperform that chosen bid.
Generally the right default for phrase, broad, and exact match campaigns, where bids are already set at the keyword level — contrast with Dynamic Bids Up and Down (Amazon PPC Bidding Strategy), which fits auto campaigns where one bid must cover many search terms of differing value.
Из тем: PPC Campaign Structure & Bidding