ACoS vs. TACoS: which number tells you if Amazon ads are working

ACoS tells you whether your ads are profitable on the sales they directly produce. TACoS tells you how dependent your whole business is on ads. You need both: ACoS to manage campaigns week to week, and TACoS to see whether advertising is actually growing your brand or just buying sales you’d have made anyway.

Most sellers learn ACoS first because it’s front and center in the Ads console. Then they hit a month where ACoS looks fine and profit still disappears. That’s usually when TACoS starts to matter.

What are the ACoS and TACoS formulas?

“Total sales” for TACoS means everything the product or account sold in the period: ad-attributed plus organic. You’ll find it in Seller Central’s Business Reports, not in the Ads console, which is one reason fewer sellers track it. There’s a short definition of each in the Shelfmate glossary.

A worked example with both numbers

For example, say a brand sells one product at $30. In a month:

• Ad spend: $1,500
• Sales Amazon attributes to ads: $5,000
• Total sales, ads plus organic: $15,000

ACoS is $1,500 ÷ $5,000 = 30%. TACoS is $1,500 ÷ $15,000 = 10%.

Same spend, two very different-looking numbers. The 30% says each ad sale costs 30 cents of every dollar. The 10% says that across the whole business, ads cost a tenth of revenue. Neither number is good or bad yet. For that you need your margin.

What is a good ACoS? Start with break-even

Your break-even ACoS is your profit margin before ad costs. If ACoS equals that number, the ad sale makes you exactly zero. Below it, you profit on ad sales. Above it, you lose money on each one.

To find it, list every per-unit cost except advertising:

$12 ÷ $30 = 40%. So in this example, break-even ACoS is 40%. A 30% ACoS leaves about 10% of the ad sale as profit. A 45% ACoS means every ad sale loses money.

Your real fees depend on category, size tier and price, and they change. As of September 2026, check your exact referral and FBA fees with the Revenue Calculator in Seller Central, and include storage, returns and inbound shipping if you want a truer number. The full method is in how to calculate true profit per unit.

This is why “what’s a good ACoS?” has no single answer. A product with a 40% margin is profitable at 30% ACoS. A product with a 20% margin loses money at 30% ACoS. Same number, opposite outcome.

What does TACoS tell you that ACoS doesn’t?

ACoS only sees ad sales. It can’t tell you whether those shoppers would have found you anyway, or whether ad sales are lifting your organic ranking. TACoS catches both, because its denominator includes organic sales.

There’s also a useful shortcut. In the example above, profit before ads was 40% of sales. Ads cost 10% of sales (the TACoS). So profit after ads is roughly 40% – 10% = 30% of total sales, before overhead. In other words:

Profit margin after ads ≈ profit margin before ads – TACoS.

That makes TACoS the number to watch for the health of the business, while ACoS is the number to watch for the health of each campaign.

Reading the TACoS trend

• TACoS falling, total sales rising: the best case. Ads are helping you rank, and organic sales are growing faster than spend.
• TACoS steady, total sales rising: healthy, scalable growth.
• TACoS rising, total sales flat: a warning. You’re spending more to sell the same amount, which often means ads are capturing sales you’d have made organically, or competition got more expensive.
• TACoS falling, total sales falling: you may have cut ads too far and lost visibility.

How targets change from launch to steady state

During a launch, you have no reviews, no sales history and little organic ranking. Many sellers deliberately run ACoS above break-even for a period, paying for sales velocity and reviews that should help organic ranking later. That’s a reasonable choice if you do it on purpose, with a budget and an end date.

What you want to see during launch isn’t a low ACoS. It’s TACoS starting to fall as organic sales pick up. If several weeks pass and organic sales aren’t growing, the launch spend isn’t doing its job and it’s time to rethink the listing, price or targeting.

Once a product is established, most brands set a target ACoS comfortably below break-even, leaving room for profit, and manage TACoS as a ceiling on how much of revenue goes to ads. Where you set those lines depends on whether you’re optimizing for growth or cash this quarter. Both are valid; just decide which one.

How often should you check ACoS and TACoS?

They move at different speeds, so check them on different clocks.

• ACoS, weekly, per campaign and per search term. This is where you act: lower bids on terms above your line, add negatives, move winners into exact match. Use at least two to four weeks of data before judging a single keyword, so late-attributed orders have time to show up.
• TACoS, monthly, per product and for the whole account. Week-to-week TACoS jumps around with promotions, stock levels and seasonality. The monthly trend is what tells you something real.

A simple spreadsheet works: one row per month, with ad spend, total sales, TACoS and total units. After three or four months, the direction is usually obvious.

Common mistakes with ACoS and TACoS

• Using someone else’s “good ACoS.” A number from a forum or course means nothing without your margin.
• Judging branded and non-branded terms together. Searches for your own brand name usually have a very low ACoS and can make an account look healthier than it is. Look at them separately.
• Chasing a low ACoS at all costs. You can get ACoS very low by only bidding on your brand name. Your sales will shrink with it.
• Ignoring attribution. ACoS uses Amazon’s attribution window, so recent days look worse until late orders are counted. Judge on a few weeks of data, not yesterday.

When a campaign’s ACoS runs above your line, the fix is usually found in the search terms. See how to read the search term report to find where the money is going.

If you only remember one thing: know your break-even ACoS for every product, and watch TACoS every month. The first keeps each campaign honest. The second tells you whether ads are building the business or just renting it sales.