ACoS in Amazon measures how much you spend on ads to generate one dollar in ad revenue. Most Amazon sellers try to keep ACoS low because a lower ACoS usually means healthier margins and better control over ad spending. A high ACoS is a warning sign. It means you’re spending more than you should for each sale, which squeezes your profits.
Amazon PPC keeps getting more expensive every year. If you do not manage your ACoS, you’ll end up losing money.
The good thing is that lowering your ACoS is not complicated once you understand what actually drives it. Here’s a quick guide to help you out.
What Is ACoS?
ACoS (Advertising Cost of Sale) is the percentage of your ad spend to ad revenue on Amazon ads, or how much you spend on ads to earn one dollar of sales. ACoS calculation is measured as ad spend ÷ ad revenue x 100. When your ACoS is low, your ads are profitable. When your ACoS is high, you are spending too much to get sales.
Strategy 1: Build a Strong Retail Foundation Before You Advertise
Most sellers think PPC problems are always about bidding or keywords, but many ACoS advertising issues start at the retail level. Your listings, your inventory health, your price, your reviews, and even how your products compare to competitors all influence how efficiently your ads perform.
A) Focus Your Advertising on Proven Performers
Most sellers accidentally waste money here. You either advertise everything or advertise only slow movers to “push them harder”
Both burn money.
In reality, your high-selling ASINs give the best ACoS because they already convert well. Nearly half of PPC performance comes down to choosing the right ASINs to advertise. Prioritize ASINs that have strong conversion, good reviews, good sales velocity, and stable inventory.
B) Fix Your Content Before You Fix Your ACoS
A lot of people forget that ACoS drops automatically when your listing converts better. Better images, clearer titles, stronger bullets, and upgraded A+ Content lead to more sales from the same clicks which means lower ACoS without touching bids.
Here’s what matters most:
1) Product Images
Think of your hero image as your “billboard.” Use dead space to highlight a key detail.
Examples you can include:
- Size or quantity
- Key feature
- Ingredients or materials
- What’s included
2) Product Title
Follow this order:
- Brand
- Product type (subcategory)
- Key feature
- Main benefit
- Size/quantity
- Primary keyword in natural order
3) Description & Bullets
Your bullets and description should answer:
- What is the product?
- Who is it for?
- What is it made of?
- What problem does it solve?
- Why is this one better?
- Any measurable detail (size, count, lifespan, material, etc.)
4) A+ Content
A+ Content typically increases conversion by 15–20%, and even more for competitive niches.
Use A+ to compare your product vs others, explain benefits visually, show lifestyle images and add instructions or compatibility details.
C) Other Retail Facts to Look Out For
These aren’t talked about enough, but they matter:
1) Inventory Levels
If you’re below 10–15 days of stock, pause ads. Continuing to advertise drains inventory too fast, triggers out-of-stock, drops your ranking and leads to higher ACoS after you restock.
2) PPC Cannibalization
If you’re already ranking organically at the top for certain keywords, reduce top-of-search placement bids or turn off those keywords temporarily.
You’re paying for traffic you would’ve received for free.
3) Traffic Seasonality
If you never look at search term volume or Search Frequency Rank (SFR), you’re missing opportunities.
For example:
- “Water bottle” peaks from Jan–March
- “Sunscreen” rises in April
- “Desk organizer” peaks in August during back-to-school season
You should adjust bids and budgets around these patterns.
Strategy 2: Overall Optimization
This strategy is all about timing and auditing. Here’s what you can do:
A) Use Dayparting to Spend at the Right Time
Dayparting means adjusting bids depending on time of day or day of week. Not every hour performs the same, and Amazon data proves it. Some categories convert best in the late evening. Others spike early in the morning.
If your data shows that evenings give you the highest conversion rate, you should raise bids between 6 PM and 11 PM so you capture more profitable traffic. If mornings consistently give weak conversion, lower your bids from 9 AM to noon so you don’t waste money. You can apply the same idea to weekends.
B) Audit Your Account Regularly to Control Waste
A proper audit helps you understand where your money is going, which parts of your account bring real results, and which sections silently drain your budget.
You should audit:
- Which campaigns have the best ROAS
- Which placements work best
- Which keywords drive the most orders
- Which match types waste money
- Which ASINs deliver the best ACoS
During an audit, you’ll often discover patterns you didn’t expect. Some campaigns look profitable on the surface but are actually carried by a few strong keywords. Some keywords get thousands of clicks and zero sales because they attract the wrong audience. You can shift your spending toward profitable areas and reduce money spent on weak ones.
Most sellers skip this because downloading reports is annoying, but weekly audits alone can save 20–30% of your wasted spend.
Strategy 3: Manage Your Bids and Budgets With Precision
Amazon PPC runs on auctions, and if you don’t understand how your bids interact with actual CPC, you’ll either overpay or fail to get impressions. Here’s how to manage your bids:
A) Optimize Your Bids the RIGHT Way
Your CPC-to-Bid ratio tells you how much of your bid Amazon is actually using. If your bid is $2 but your actual CPC is only $0.30, Amazon is using just a small fraction of your bid. This means small adjustments (like lowering the bid to $1.80) won’t make any difference. The keyword is already sitting far above the auction floor. In that case, only a big drop will create real change.
The simplest way to apply this is to follow two rules. If a keyword is performing extremely well and the CPC/Bid ratio is high, you increase the bid. If a keyword is performing poorly and your CPC is far below your bid, you reduce the bid by 30% or more.
B) Optimize Your Budgets the Smart Way
A clean budget optimization starts with identifying which campaigns sit far above your target ACoS. If a campaign is performing at 1.5–2× your target ACoS, reduce its budget significantly until you fix it.
Next, look for campaigns that consistently deliver stable sales at or below your target ACoS. These are your winners. Increasing their budgets allows you to scale profitably without raising your overall spend.
You should also be careful with campaigns that generate very few monthly orders. If a campaign delivers fewer than 3-5 orders per month, it is not contributing enough to justify aggressive spend. Lowering their budgets frees up money for campaigns that actually bring measurable results.
All this can improve account ACoS in less than 24 hours.
C) Adjust Your Placements for Maximum Efficiency
Amazon offers three main ad placements: top of search, rest of search, and product detail pages.
Top of search is the most expensive placement because it’s the first thing customers see. Some categories, especially beauty, personal care, and high-urgency items, convert extremely well here. A higher top-of-search placement modifier can be a profitable move.
Rest of search is typically cheaper and works better for categories where customers scroll more, such as home goods, kitchen tools, and decor. These shoppers take more time comparing products, so they often convert even if your ad appears mid-page.
Product detail page placement behaves differently. It shows your ad on a competitor’s listing. This placement works well in categories where customers compare products, like supplements, pet supplies, or electronics accessories.
Look at your data when deciding placement. See where your conversions actually come from. If top of search drains the budget but doesn’t convert well for a certain product, reduce the modifier. If product detail pages consistently give you sales at a low ACoS, increase the modifier there so you appear more often.
Strategy 4: Strengthen Your Keywords and Audience Targeting
Your keywords decide how relevant your ads are, and relevance directly impacts CPC and ACoS. Here’s how to strengthen your keywords:
A) Use Long-Tail Keywords to Get Cheaper, Better Converting Traffic
Long-tail keywords have lower search volume, but the customers using them know exactly what they want. That’s why these keywords often convert better and cost less.
Long-tail keywords are also a great way to avoid fighting with big brands for expensive broad terms.
You can find long-tail keywords through automatic campaigns, broad match campaigns, customer search term reports, and even customer Q&A sections.
B) Negate Search Terms Frequently to Remove Bad Traffic
Amazon now generates more search term variations than ever before, even for exact match keywords. This means your ads can appear for unrelated or weak search terms without you noticing. If you don’t negate these terms, they silently drain your budget every single day.
There are two main ways to approach negation.
The first is relevance-based negation, which means removing search terms that have nothing to do with your product. Relevance-based negatives keep your ads in front of the right audience and prevent accidental clicks that never convert.
The second approach is CAC-based negation. This is where you look at performance data and remove keywords that consistently waste money. If a search term spends (even though relevant) 4-5 times your target cost of acquisition and still brings zero sales, it needs to be shut down immediately.
Strategy 5: Use Automation the Smart Way
Automation is one of the easiest ways to control ACoS without spending hours manually adjusting campaigns. You don’t need complicated or expensive software to do this. What you really need are simple rules and the discipline to set them up properly.
A) Automate Simple Rules to Keep Performance Stable
Automated rules are designed to protect your account when you’re not actively working. Amazon Ads gives you the option to create your own rules, and even the most basic ones can make a big difference. For example, if a keyword goes far above your target ACoS, a rule can automatically lower its bid without waiting for you to check the campaign. Automation works best when rules are simple and based on your goals.
B) Automate Keyword Management to Reduce Manual Work
Without automation, you would need to manually add new converting keywords, pause bad ones, and monitor bid changes every single day. You can set rules to automatically harvest new keywords from search terms that consistently drive orders to save time. You can also automate the removal of search terms that keep spending money without conversions.
Automation also helps you maintain healthy bids. If a keyword starts losing performance, a rule can automatically reduce the bid to stop unnecessary spend.
C) Use Predictive Alerts to Prevent ACoS Spikes
Predictive alerts notify you before issues get worse. You can set alerts for low inventory, sudden spend spikes, keyword performance drops, and seasonal demand increases. This prevents ACoS spikes before they happen.
Summary
Lowering Amazon ad costs in 2025 is not about cutting bids. It’s about knowing how your products sell and customers behave, and how your retail signals and advertising work together.
If you need help reviewing your listings, adjusting your Amazon ACoS strategy, or building a custom PPC plan for your brand, Enso Brands can help you out. Contact us for more information about our services.
