Amazon Bidding Strategies Explained: Down Only, Up and Down, and Fixed Bids

Amazon Sponsored Products offers three campaign-level bidding strategies: Dynamic bids - down only, Dynamic bids - up and down, and Fixed bids. Down only lets Amazon cut your bid when a click looks less likely to convert. Up and down also lets Amazon raise it, by up to 100% for top-of-search placements and up to 50% elsewhere. Fixed bids uses your exact bid every time. For most sellers, down only is the safest default, up and down suits proven, profitable campaigns, and fixed bids is a tool for controlled tests.

The strategy you pick changes what you actually pay per click, so it matters as much as the bid number itself. Here is how each one works, with examples.

Where to find the bidding strategy setting

In the Amazon Ads console, the bidding strategy is set at the campaign level. You choose it when you create a Sponsored Products campaign, and you can change it later by opening the campaign, going to Campaign settings, and editing the Campaign bidding strategy section. The same panel holds your placement adjustments (top of search, rest of search, and product pages), which work together with the strategy. If you have not read it yet, our guide to Amazon placement bid adjustments covers that side in detail.

Sponsored Brands and Sponsored Display have their own bid controls and optimization options, which differ from Sponsored Products. This article focuses on Sponsored Products, where most sellers spend the majority of their budget.

Dynamic bids - down only

With down only, Amazon may lower your bid in real time when its model predicts a click is less likely to turn into a sale. It never raises your bid above what you set. If your keyword bid is $1.20, the most you will be charged for that keyword is $1.20 (plus any placement adjustment you add), and in many auctions you will pay less.

This is the default for new campaigns, and for good reason. It protects you from overpaying on low-intent traffic while you learn what converts. The trade-off is that you may lose some impressions in auctions where Amazon decided to lower your bid, so volume can be a bit lower than with the other two strategies.

When to use down only

• New campaigns and new products, where you do not yet have conversion data.
• Auto campaigns and broad research campaigns, which pick up a lot of loosely related traffic.
• Any campaign where ACoS is above your target and you want a safety net while you adjust bids.
• Accounts with tight margins, where overpaying for a click quickly wipes out profit.

Dynamic bids - up and down

Up and down gives Amazon permission to raise your bid when a click looks more likely to convert and to lower it when it looks less likely. Amazon caps the increase at 100% for top-of-search (first page) placements and 50% for all other placements. So a $1.00 bid could become as much as $2.00 at the top of search and $1.50 on other placements, before placement adjustments are applied.

That cap stacks with placement adjustments, which is where sellers get surprised. If you set a 50% top-of-search adjustment and use up and down, a $1.00 bid can first become $1.50 from the placement adjustment, and then Amazon can raise it by up to 100% on top, for a maximum of $3.00. Your CPC report will look nothing like your keyword bid.

When to use up and down

• Exact-match campaigns on proven keywords with ACoS comfortably below target.
• Branded campaigns where conversion rates are high and you want to hold the top spot.
• Launches where you have decided to pay more for velocity and have set a budget limit for it.
• Peak events like Prime Day or Black Friday, when conversion rates rise and aggressive bids can pay off.

Fixed bids

Fixed bids means Amazon uses your exact bid, adjusted only by any placement adjustments you set. It will not raise or lower it based on conversion likelihood. That makes it predictable, and it can win more impressions than down only because Amazon is not cutting your bid in auctions it judges weaker.

The downside is that you pay full price for every click, including the low-quality ones. Fixed bids works best when you want clean, controlled data, for example when testing a new placement or comparing bid levels, or when you are running a short visibility push and accept the efficiency cost.

Worked example: the same keyword under each strategy

Say your exact-match keyword bid is $1.00, and you have a 50% top-of-search placement adjustment and 0% on rest of search and product pages. Here is the maximum Amazon could charge per click under each strategy.

Remember these are ceilings. Amazon runs a second-price style auction, so you often pay somewhat less than your maximum, close to what it takes to beat the next advertiser. Our explainer on how the Amazon ads auction works walks through why. Still, the ceiling tells you your risk. Under up and down, this keyword could cost three times its bid on the most competitive placement.

Rule-based bidding

Amazon also offers rule-based bidding for some eligible Sponsored Products campaigns, where you set a ROAS guardrail and Amazon adjusts bids to try to stay at or above it. Eligibility depends on the campaign having enough conversion history, and availability can vary by marketplace. If you see the option in your console, treat it like up and down with a safety rail: test it on a campaign with steady data and compare results over at least two to four weeks before rolling it out.

A simple decision framework

Use these rules as a starting point and adjust once you have data. They assume you already know your break-even ACoS. If you do not, run your numbers through the break-even ACoS calculator first.

1. New campaign or new product: start on down only.
2. After 2 to 4 weeks, if a campaign's ACoS is at least 20% below target and it has 10 or more orders, test up and down.
3. If ACoS on up and down climbs above target for two consecutive weeks, switch back to down only before you cut bids.
4. Use fixed bids for experiments where you need clean data, and set an end date for the test.
5. Before a peak sales event, consider moving your best exact-match campaigns to up and down for the event window only.

Common mistakes with bidding strategies

• Turning on up and down plus a large top-of-search adjustment on an unproven campaign. The combined multiplier can triple your CPC.
• Judging a strategy after a few days. Conversion data lags, and Amazon attributes Sponsored Products sales for sellers over a 7-day window, so give changes at least a week.
• Changing the strategy and the bids at the same time. You will not know which change caused the result.
• Forgetting the strategy exists. Many accounts have old campaigns still on up and down that no longer deserve it.

Bidding strategy is one lever. The other big ones are the bid amount and the budget. If you want a formula for setting the bid itself, see how to calculate Amazon PPC bids.

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