How to Lower ACoS on Amazon: 8 Proven Methods (2026)

ACoS is a symptom, not a diagnosis. High ACoS can mean your targeting is sloppy, your listing doesn't convert, your bids are wrong for your margins, or your campaign structure is fighting itself. Lowering it requires figuring out which problem you actually have — and most sellers never bother with that step.

After managing PPC for 50+ brands with $205M+ in total Amazon sales, here are the 8 methods that consistently lower ACoS without sacrificing volume. These aren't theories — they're what we run every day across our portfolio.

1. Negative Targeting: Cut the Waste First

This is where we start with every account, every time. Before you optimize anything, you need to stop paying for traffic that will never convert.

Pull your search term report. Look for:

• Terms with meaningful spend and zero conversions

• Irrelevant queries that Amazon's broad match decided to show you on

• Competitor brand names where you're hemorrhaging clicks

Negate these at the right match level — exact negative for specific terms, phrase negative for categories of waste. We've written an entire guide on negative targeting because it's that foundational.

The impact is immediate. We regularly see ACoS drop 15-25% in the first two weeks just from cleaning up search terms that should have been negated months ago.

2. Listing Optimization: Higher CVR = Lower ACoS

This is the lever most PPC managers completely ignore because it's "not their job." But the math is simple: if your listing converts at 10% instead of 8%, your ACoS drops by 20% without changing a single bid.

Every click costs the same whether it converts or not. Improving your conversion rate makes every dollar of ad spend more efficient.

Where to focus:

• Main image — The highest-leverage element on your listing. A better main image improves CTR from search results and conversion rate on the page.

• Title structure — Front-load your primary keyword and key differentiator

• Bullet points — Benefit-first framework, mobile-optimized (only first 3 show on mobile)

• A+ Content — Comparison charts and problem/solution modules convert. Brand story essays don't.

Test everything through Manage Your Experiments. We've run 10,000+ A/B tests and the results regularly surprise us. What you think will convert often doesn't.

3. Keyword Harvesting from Auto Campaigns

Your auto campaigns are a data goldmine — if you actually mine them.

Here's the process:

• Run auto campaigns with controlled budgets

• Review search term reports weekly

• Identify converting search terms with strong ACoS

• Graduate those terms into exact match campaigns with dedicated bids

• Negate the graduated terms from the auto campaign to avoid competing with yourself

The mistake most sellers make: they run auto campaigns and never harvest. So they keep paying discovery-level bids for terms that have already proven themselves. Or worse — they harvest but don't negate from auto, so they're bidding against themselves on the same keyword across two campaigns.

This creates a continuous improvement loop. Your auto campaigns discover. Your manual campaigns scale. Your negatives prevent overlap. Each piece feeds the others.

4. Bid Optimization: Stop Guessing, Use the Data

Bid optimization isn't "lower all bids to reduce ACoS." That's how you kill volume and tank organic rank simultaneously.

Smart bid optimization means:

• Bid to your target ACoS by keyword, not by campaign. A keyword converting at 8% ACoS and a keyword converting at 45% ACoS shouldn't have the same bid just because they're in the same campaign.

• Use bid ranges based on conversion data. Keywords with 20+ conversions give you statistically reliable data. Keywords with 2 conversions are noise. Adjust confidence accordingly.

• Increase bids on winners. Most sellers only lower bids on losers. But your best keywords often have room to scale — higher bids mean more impressions, more clicks, and if the conversion rate holds, more profitable sales.

• Factor in organic rank impact. Aggressive PPC on a keyword can boost organic rank, which gives you free sales. Sometimes a 35% ACoS keyword is worth running because it's driving organic rank that generates far more revenue than the ad itself.

This is where TACoS matters more than ACoS — but we'll get to that.

5. Dayparting: Stop Paying for Dead Hours

Not all hours convert equally. Depending on your category, there can be significant performance differences between peak and off-peak hours.

Analyze your campaign performance by hour of day:

• When does your conversion rate peak?

• When does CPC spike without corresponding conversions?

• Are there dead zones where you're spending but not selling?

For many categories, we see conversion rates drop significantly between midnight and 6 AM while CPCs stay relatively stable. That's pure waste. Reducing bids or pausing campaigns during these hours can lower ACoS without losing meaningful volume.

Caveat: dayparting data needs volume to be reliable. If you're spending $50/day, you don't have enough data to daypart effectively. This strategy works best for brands spending $500+/day where hourly patterns become statistically significant.

6. Placement Adjustments: Bid Where You Win

Amazon lets you adjust bids by placement: top of search, rest of search, and product pages. Most sellers either ignore this or apply blanket adjustments without data.

Here's how to use it:

Pull your placement report. For each campaign, look at:

• Top of search: Usually highest CPC but often highest conversion rate. If your conversion rate on top of search is 2-3x your average, increasing the placement modifier here can dramatically lower ACoS because the higher conversion rate more than offsets the higher CPC.

• Product pages: Often the cheapest clicks but lowest conversion. These are shoppers browsing competitors who see your Sponsored Product ad. Conversion depends heavily on how your product compares to the one they're already looking at.

• Rest of search: The middle ground. Usually moderate CPC and moderate conversion.

The play: increase bids on placements where your conversion rate justifies it, decrease where it doesn't. This sounds obvious, but most accounts we audit have zero placement adjustments — they're bidding the same regardless of where the ad appears.

7. Campaign Restructuring: Fix the Architecture

Bad campaign structure is a silent ACoS killer. The symptoms:

• Keywords competing against each other across campaigns

• Auto and manual campaigns targeting the same terms

• Broad, phrase, and exact match all running on the same keyword without clear roles

• Single-product campaigns mixed with multi-product campaigns with no logic

The structure that works for most brands at scale:

• Auto campaigns — Discovery only. Low bids. Harvest weekly.

• Broad/phrase campaigns — Research layer. Moderate bids. Graduate winners, negate losers.

• Exact match campaigns — Performance layer. Aggressive bids on proven keywords.

• Defensive campaigns — Brand terms. These should have the lowest ACoS in your account.

• Competitor campaigns — Offensive. Expect higher ACoS. Evaluate on incrementality, not efficiency.

Each layer has a clear job. When campaigns have unclear roles, budget leaks between them and you can't diagnose what's working.

Restructuring is painful — it means pausing campaigns with historical data and rebuilding. But every time we've restructured a messy account, ACoS dropped within 4-6 weeks because the data finally became clean enough to optimize against.

8. TACoS-Focused Strategy: The Metric That Actually Matters

ACoS measures your ad efficiency. TACoS (Total Advertising Cost of Sale) measures your ad spend as a percentage of total revenue — including organic sales.

Why this matters: the goal isn't low ACoS. The goal is growing total revenue profitably.

A 30% ACoS campaign that drives organic rank improvements might have a TACoS impact of only 12% because every sale from that keyword also improves your organic position, generating sales you don't pay for.

Conversely, a 15% ACoS campaign on branded terms looks great on paper but isn't driving any incremental sales — those customers would have found you organically anyway. Your ACoS is low but the spend is mostly wasted.

TACoS-focused strategy means:

• Track the ratio of organic to paid sales over time. If TACoS is rising while ACoS stays flat, your organic rank is declining and you're becoming more dependent on ads.

• Accept higher ACoS on keywords that drive organic rank. This is a short-term investment with compounding returns.

• Question the value of low-ACoS branded campaigns. Are they truly incremental, or are you paying for sales you'd get anyway?

• Measure success over 90-day windows, not weekly snapshots. Organic rank impact from PPC takes weeks to materialize.

The brands in our portfolio that scale fastest are the ones that shift from obsessing over ACoS to managing TACoS. It's a fundamental change in how you think about ad spend — from a cost to be minimized to an investment to be optimized.

What To Do Next

If you're doing $50K+/month on Amazon and your ACoS is higher than it should be — or you've been lowering ACoS by cutting spend instead of improving efficiency — there's likely significant opportunity in your account.

Book a free strategy call — We'll analyze your campaign structure, search term data, and listing conversion rates. You'll walk away with a clear picture of where your ACoS is leaking and what to do about it.

Hunter Harris is the founder of GigaBrands, an AI-assisted Amazon growth agency managing 50+ brands with over $205M in total Amazon sales.