To lower ACoS on Amazon, cut wasted spend with negative keywords, lower bids on high-ACoS search terms while raising them on profitable ones, and improve your listing so more clicks convert. Tighter campaign structure and dayparting sharpen results further. ACoS falls when every click gets cheaper or converts more often.
TL;DR
- ACoS = ad spend / ad sales. You lower it by spending less on losers or converting more of what you already pay for.
- Five levers: negative keywords, bid tuning, listing conversion, dayparting, and campaign structure.
- Conversion is the quiet lever. A better listing lowers ACoS at the same bid, and most sellers ignore it.
- Amazon advertising is now a core cost of doing business, with US retail media spend passing $60 billion, per eMarketer.
- Doing this by hand every week is real work, which is why many sellers automate bid and keyword management so ACoS stays low without daily babysitting.
What is ACoS and why does it matter?
ACoS, or Advertising Cost of Sales, is the percentage of your ad-driven revenue that you spend on ads. The formula is simple: ad spend divided by ad sales, times 100. If you spend $25 on ads and make $100 in ad sales, your ACoS is 25%. Lower is more efficient, but lower is not always the goal, because zero ads means zero ad-driven growth.
The number that actually matters is your break-even ACoS, which equals your profit margin before advertising. If your product carries a 30% margin, an ACoS above 30% means you are losing money on those ad sales. Below 30%, you are profitable. According to the Jungle Scout State of the Amazon Seller Report, advertising is one of the top expenses sellers cite, so controlling ACoS is not a nice-to-have. It is the difference between a profitable product and a leaky one.
What is a good ACoS on Amazon?
A good ACoS is any figure that sits below your break-even ACoS and matches your goal for that product. There is no single right number. A launch product might run a 50% ACoS on purpose to buy ranking and reviews, while a mature product with strong organic sales might target 15%. Both can be correct.
| Product stage | Typical ACoS goal | Why |
|---|---|---|
| New launch | 40% - 60% | Buying visibility and early sales velocity |
| Growth | 25% - 40% | Scaling while staying near break-even |
| Mature | 15% - 25% | Defending rank, protecting margin |
| Liquidation | Whatever moves stock | Clearing inventory beats holding it |
Judge ACoS against the job the product is doing, not against a benchmark you read somewhere. Amazon's advertising business has grown into a top revenue segment, reaching over $50 billion in ad revenue in a recent year per Amazon's earnings reporting, which tells you how competitive the auction has become. In that environment, a disciplined ACoS target per product beats one blanket rule.
How do negative keywords lower ACoS?
Negative keywords lower ACoS by stopping your ads from showing on searches that waste money. Every campaign accumulates search terms that get clicks but rarely convert. Left alone, they quietly drain your budget and inflate your ACoS. Adding them as negatives redirects that spend toward terms that actually sell.
Here is the workflow:
- Pull your search-term report in Amazon Seller Central, filtered to the last 30 to 60 days.
- Sort by spend with zero or few orders. These are your money leaks.
- Add high-spend, no-sale terms as negative exact or negative phrase keywords.
- Repeat weekly. New junk terms appear constantly as your campaigns discover fresh queries.
This is the single fastest way to cut ACoS in week one, because you are removing pure waste rather than gambling on bid changes. Amazon Ads confirms that search-term reports are the primary source for finding and excluding irrelevant traffic. The catch is that it never stops. A growing catalog generates hundreds of new search terms a week, and reviewing them all by hand is where most sellers fall behind.
How should I tune bids to lower ACoS?
Tune bids by moving budget toward what converts and away from what does not, rather than cutting spend across the board. ACoS improves when you reallocate, not just when you spend less. Blanket bid cuts lower ACoS on paper but often tank sales and organic ranking with it.
Follow a simple rule set:
- High ACoS, enough clicks: lower the bid in steps of 10% to 15%, not all at once.
- Low ACoS, strong conversion: raise the bid to capture more of that profitable traffic.
- High ACoS, few clicks: wait. You do not have enough data to judge it yet.
- Good ACoS but low impressions: raise the bid to win more placements.
The mistake to avoid is judging a keyword on too little data. A term with three clicks and no sales is not a proven loser. Give keywords 10 to 15 clicks before you act, and change bids in increments so you can measure the effect. For the full framework behind campaign types and match settings, see the Amazon PPC guide and the 2026 PPC strategy breakdown.
Does improving my listing lower ACoS?
Yes, and it is the lever most sellers overlook. Because ACoS is ad spend divided by ad sales, a higher conversion rate lowers ACoS at the exact same bid. If your listing converts 8% of clicks instead of 5%, you make more sales per dollar of spend without touching a single campaign setting.
The elements that move conversion most:
- Main image and gallery. Images drive click-through and post-click confidence more than any other element.
- Price and Buy Box. An uncompetitive price kills conversion no matter how good the ad is. See how to win the Amazon Buy Box.
- Reviews and rating. Social proof is a direct conversion multiplier.
- Title and bullets. Clear benefit-first copy reassures the shopper the click was right.
According to Amazon Ads, a strong product detail page lifts both conversion and the organic ranking that ads feed. This is why chasing bids alone hits a ceiling. If your listing converts poorly, you are paying to send traffic to a page that leaks, and no bid tweak fixes a leaky page. Full technical detail lives in amazon acos explained.
What is dayparting and does it help?
Dayparting is adjusting ad spend by time of day or day of week to concentrate budget when your shoppers actually buy. It helps because conversion rates are not flat across a 24-hour cycle. If your product converts best on weekday evenings and barely at 3 a.m., spending equally across both wastes money and raises ACoS.
To use it:
- Analyze your hourly and daily conversion data over several weeks.
- Identify low-conversion windows where clicks come but orders do not.
- Reduce or pause bids during those windows and shift budget to peak hours.
Dayparting is a refinement, not a foundation. Fix negative keywords, bids, and conversion first, then use dayparting to squeeze out the last few points of ACoS. The honest limitation is that Amazon's native tools make hourly bid control clunky, and doing it manually across dozens of campaigns is impractical for most sellers. This is one area where automation earns its keep, because a rules engine can adjust bids hour by hour in ways a human never could.
How does campaign structure affect ACoS?
Clean campaign structure lowers ACoS by giving you control over where budget flows and clear data to act on. Messy accounts, where hundreds of keywords sit in a few sprawling campaigns, make it nearly impossible to see what is working. You cannot lower ACoS on a term you cannot isolate.
A structure that keeps ACoS controllable:
| Campaign type | Job | ACoS control |
|---|---|---|
| Auto | Discover new converting search terms | Harvest winners, negate losers |
| Broad / phrase | Scale keywords found in auto | Feed proven terms more budget |
| Exact | Defend and scale top performers | Tightest bid control, lowest ACoS |
| Brand defense | Protect your own brand searches | Cheap, high-converting traffic |
The principle is a funnel. Auto and broad campaigns discover what works, and you graduate winning search terms into tightly bid exact campaigns where ACoS is easiest to control. Losers get negated along the way. This structure turns a chaotic account into a system, but it also multiplies the number of moving parts you have to manage. More campaigns means more search-term reports, more bids, and more negatives to review every week.
How often should I optimize to keep ACoS low?
Optimize at least weekly, and daily during launches and peak seasons. Amazon is a live auction where competitors change their bids constantly, so an account you tuned last month has already drifted. ACoS is not something you set once. It creeps up the moment you stop watching.
A realistic weekly routine looks like this:
- Pull and review search-term reports, adding negatives.
- Adjust bids up on profitable terms and down on high-ACoS ones.
- Check that budgets are not capping out on winning campaigns.
- Watch for listing or price changes that hurt conversion.
Multiply that routine across 20, 50, or 100 products and it becomes a full-time job. This is the wall most sellers hit. The tools tell you what is wrong, but you still have to do every negative, every bid, every week, forever. That gap between insight and action is exactly where an operator model changes the math.
Frequently asked questions
How do I lower my ACoS on Amazon?
Add negative keywords to cut wasted spend, lower bids on high-ACoS terms, raise bids on profitable ones, and improve listing conversion so each click is worth more. Tighter campaign structure and dayparting help too. Small, frequent adjustments beat rare big ones.
What is a good ACoS on Amazon?
A good ACoS is any figure below your break-even ACoS, which is your profit margin before ad spend. Many sellers target 15% to 25% on established products and accept higher ACoS during launches to build ranking. There is no universal number.
Do negative keywords lower ACoS?
Yes. Negative keywords stop your ads from showing on searches that click but rarely convert, which cuts wasted spend directly. Reviewing your search-term report weekly and adding poor performers as negatives is one of the fastest ways to bring ACoS down.
Does improving my listing lower ACoS?
Yes, often more than bid changes do. ACoS is spend divided by ad sales, so a higher conversion rate lowers ACoS at the same bid. Better images, titles, price, and reviews turn more clicks into orders, which improves ad efficiency automatically.
Should I lower bids to reduce ACoS?
Lower bids only on keywords with high ACoS and enough click data to judge them. Cutting bids across the board reduces spend but also sales and ranking. The goal is reallocating budget toward profitable terms, not just spending less.
How often should I adjust Amazon PPC to control ACoS?
Review search-term reports and bids at least weekly, and check daily during launches or peak seasons. Amazon is a live auction where competitors change bids constantly, so ACoS drifts if you leave campaigns untouched for weeks at a time.
Lowering ACoS is simple to understand and exhausting to do by hand. Jinnify manages your negative keywords, bids, and dayparting on autopilot, and it improves the listing conversion that ACoS depends on - so your ads stay profitable without the weekly grind. Start for free with a 7-day trial, no card required.
Author: The Jinnify Team - Amazon growth and automation specialists Published: 2026-07-08 | Updated: 2026-07-08 Sources: Amazon Ads, Jungle Scout State of the Amazon Seller Report, eMarketer, Amazon Company News