What is the max profitable bid?

It's the highest cost per click at which a keyword still makes a profit: average price × conversion × break-even ACoS. With a $30 product, 10% conversion and a 25% break-even ACoS, the cap is $0.75. Above it, each sale costs more in ads than the margin it leaves.

Why does the max profitable bid show “—”?

Data is missing: the keyword or target had fewer than 2 orders in the last 30 days, or the product has no cost registered. Without cost there's no break-even ACoS, and without orders the conversion rate isn't reliable.

Can automations raise a bid above the cap?

No. Automated rules, the Raise bid recommendation and bid changes applied by Vision stop at the cap. Lowering bids is always allowed, and you can still type a bid above the cap manually; the screen then shows a “bid above” badge.

How does EcomVision know the problem is conversion and not the bid?

It compares the term's cost per click and conversion with the account average and with the same product's conversion across the rest of the account. Average click cost and low conversion on both the term and the product = a conversion problem (review the listing). A product that converts well on other terms = a term or campaign problem.

Why do rules wait 7 days after a listing is published?

Two changes at once (listing and bid) make it impossible to tell which one worked, and Amazon attributes sales within 7 days. The wait applies to listings published through EcomVision.

What changes for campaigns in a launch?

While the launch strategy is active and within its deadline, rules don't lower bids or pause those campaigns, the max profitable bid doesn't cap increases, and recommendations use the launch ACoS target. Negating terms that spent without selling still applies.

Max Profitable Bid and High-ACoS Safeguards

Cutting every bid drops ACoS for a week and takes sales and search rank down with it. What works is different: cut the waste, know how far each bid can go before it loses money, and don't mistake a conversion problem for a bid problem. EcomVision now shows the Max profitable bid for every keyword and target, and automations respect that cap, along with four more safeguards.

What the max profitable bid is and how it's calculated

Each click costs the bid (at most) and brings, on average, a fraction of a sale. The max profitable bid is the highest bid at which that math still comes out positive:

max profitable bid = average price × conversion rate × break-even ACoS

Break-even ACoS is the margin before ads: what's left of the sale after product cost, Amazon fees and taxes. Example: a $30 product, 10% conversion and a 25% break-even ACoS give a cap of 30 × 0.10 × 0.25 = $0.75 per click. Above that, every sale the keyword brings costs more in ads than the margin it leaves.

EcomVision uses the last 30 days of each keyword or target and the product's real profit (the same as the P&L). It only shows up with enough data: at least 2 orders in the period and the product cost registered.

Where to see it in EcomVision

Open Campaigns and click a campaign name.
On the Keywords and Targets tabs, the Max profitable bid column sits next to Bid. Hover the header to read the explanation.
When the current bid is above the cap, a bid above badge appears.

Campaign detail in EcomVision, Keywords tab, with the Max profitable bid column next to Bid and the bid above badge on two keywords. — **Max profitable bid** column in the campaign detail (demo account, 30 days). Two keywords show the **bid above** badge.

In the demo account, “insulated water bottle” has a $1.71 bid and a $1.14 cap, and “32 oz water bottle” has a $1.30 bid and a $1.12 cap: both are already paying more per click than the sale leaves in margin. “vacuum insulated bottle”, at $0.79 with a $1.18 cap, has room to grow profitably.

Automations never go above the cap

The cap isn't just information. Automated rules (by campaign, by keyword or target and by product), the Raise bid recommendation in the Keyword Optimizer and bid changes applied by Vision never raise a bid above the cap. When a rule says +20% and that would pass the limit, the bid stops at the cap and the run summary says so.

Lowering bids is always allowed, and so is manual editing: you can type a bid above the cap (the badge will flag it). To see how rules work, check Ads Automation.

When the problem is conversion, not the bid

ACoS = cost per click ÷ (conversion × price). If the click costs what it usually costs in the account and conversion is far below, lowering the bid only cuts reach and doesn't fix the cause. The Keyword Optimizer now separates the two cases:

The whole product converts poorly (the term and the product across the account below 60% of the account average, with cost per click at the average): the card becomes low conversion, explains the cause, links to View the product → and suggests only a light 10% bid cut. The fix is the title, images and bullets, with the Listing Optimizer.
The same product converts well on other terms or campaigns: the listing isn't the culprit. The card stays Lower bid and explains the problem is the term or the campaign.

Promoting a term now negates it at the source

When a search term sells well in an auto or broad campaign, the right move is to "graduate" it: create it as an exact keyword with its own bid and negate it in the source campaign, so the two don't compete for the same click. Promote (exact harvest) now does both: it creates the exact keyword in the product's harvest campaign and an exact negative in the source campaign. For a promoted product (ASIN), it creates the negative product target. It only negates what actually made it into the harvest campaign, and the confirmation dialog tells you first.

One change at a time: the 7-day wait

Changing the listing and the bid in the same week makes it impossible to tell which change worked, and Amazon takes a few days to attribute sales. So:

If the product listing was published through EcomVision in the last 7 days, automated bid rules for that product's campaigns wait until 7 days have passed.
The campaign detail shows a warning bar, and "changed Nd ago" appears under any bid that changed in the last week.
Bid recommendations end with a note to wait about 7 days.

Launches: planned high ACoS, with a deadline

In a launch, accepting an ACoS above break-even for a while is a strategy: it drives sales, reviews and search rank. While a launch strategy is active and within its deadline, automated rules don't lower bids or pause its campaigns (negating terms that spent without selling still applies), the max profitable bid doesn't cap increases, and recommendations use the launch ACoS target and say the campaign is in launch until its end date. When the deadline ends, everything goes back to normal.

Things to keep in mind

"—" in the Max profitable bid column isn't zero. It means fewer than 2 orders in 30 days or no product cost registered. Add the cost for the cap to show up.
The cap always uses 30 days, even if the screen is set to 7 or 14 days: it's the same window that caps automations.
A high cap isn't an instruction to raise the bid. It tells you how far you can go profitably; raising is still your call (or the rule you created).
The 7-day wait only sees listings published through EcomVision. Edits made directly in Seller Central don't show up.
For the full picture on lowering ACoS, see also how to lower ACoS on Amazon and how to add negative keywords without losing sales.

Sources

Amazon Ads — official site (sales attributed within 7 days)
EcomVision — Keyword Optimizer (feature)
EcomVision — Ads Automation (feature)

Max profitable bid: the highest bid at which a click still makes money (plus 4 safeguards against high ACoS)