TACOS vs ACOS: Which Number Tells You If Your Amazon Ads Are Working

ACOS tells you whether your ad clicks pay for themselves. TACOS tells you whether your ads are growing the whole business. ACOS is ad spend divided by the sales your ads claim. TACOS is the same ad spend divided by all your sales, organic included. A campaign can hold a healthy 30% ACOS while TACOS climbs every month, which means ads are taking over sales you used to get for free. So the honest answer is that neither number works alone. Use ACOS to judge each campaign against break-even, and use TACOS, read next to total sales, to judge whether advertising is working for the business.

If your ad spend keeps rising while total sales sit flat, this is usually the gap you are looking at. The campaign dashboard looks fine. The bank account does not.

Below we cover what each metric really measures, the one formula that connects them, a worked example of ACOS staying flat while profit drops by a quarter, what a healthy TACOS looks like at each stage of a product's life, and the mistakes we see most often in the accounts we audit.

ACOS and TACOS in one minute

Both metrics put ad spend on top. The difference is what goes underneath.

ACOS is a campaign tool. It tells you whether a keyword, a target or a placement earns more than it costs. If you have not worked out your break-even ACOS yet, start with our break-even ACOS guide, because every ACOS number is meaningless without it.

TACOS is a business tool. It tells you how much you pay in advertising for every dollar of revenue the product brings in, wherever that revenue came from. Amazon does not show it in Campaign Manager, which is one reason so many sellers never track it.

The formula that connects them

Here is the link most sellers miss. Divide and multiply by ad sales and you get:

TACOS = ACOS × (ad sales ÷ total sales)

The second part is your ad share: the slice of total sales that came through an ad click. If ACOS is 30% and ads drive 40% of your sales, TACOS is 30% × 40% = 12%.

This tells you there are exactly two ways to bring TACOS down. You can make ads more efficient (lower ACOS), or you can make the business less dependent on ads (lower ad share, because organic sales grow). The second one is where the real profit sits, and ACOS cannot see it at all.

It also tells you there are two ways for TACOS to go up. One is ACOS rising, which you will spot in Campaign Manager. The other is ad share rising while ACOS stays put, which you will not spot unless you track TACOS. That second one is the quiet margin killer.

Worked example: ACOS holds at 30%, profit drops by a quarter

We will use the same $29.99 FBA kitchen product from our profit calculator. After Amazon fees and product cost it leaves $10.95 per sale before ads, which is 36.5% of the price. That is its break-even ACOS.

Say it sells $60,000 a month. In month one, ads drive $24,000 of that at a 30% ACOS. Two months later total sales are still $60,000 and ACOS is still 30%. On the campaign dashboard nothing has changed. Here is what happened underneath.

The extra $3,600 of ad spend bought no extra revenue. It bought $12,000 of sales the product was already getting organically. Profit after ads fell from $14,700 to $11,100, a 24.5% drop, while every campaign stayed comfortably under break-even.

This happens all the time. A competitor takes your organic spot on a main keyword, a ranking campaign is switched off, or a branded campaign starts catching shoppers who were already searching for you. ACOS stays steady because the ads are still converting. They are just converting people you would have had anyway.

There is a useful shortcut in the table. Profit before ads as a percent of sales, minus TACOS, gives you margin after ads: 36.5% − 12% = 24.5%, and 36.5% − 18% = 18.5%. That is why TACOS is the ad metric that ties most directly to profit.

So which number tells you if your ads are working?

Read them together, along with total sales. Each combination tells a different story.

The second row surprises people. During a ranking push it is normal for ACOS to sit above break-even, because you are paying for rank, not just for today's sale. If organic sales are climbing at the same time, TACOS falls and the push is working. Judge it on ACOS alone and you will switch off the campaign that is building your organic business.

The last row is a different problem entirely. If ACOS is rising, work through why ACOS goes up before you change a single bid.

TACOS can fool you too

TACOS is still a ratio, and ratios can improve while dollars shrink. Take the same product at $60,000 a month, $30,000 from ads at 30% ACOS, so 15% TACOS. The seller cuts bids hard on the main keyword. Spend falls to $5,400 and ACOS drops to 24%. But the product slips down the page for that keyword, organic sales fall too, and total sales land at $42,000.

TACOS improved from 15% to 12.9%. ACOS improved from 30% to 24%. Profit after ads fell from $12,900 to $9,930. Both ratios looked better and the business made $2,970 less that month. This is why we never look at TACOS without total sales next to it.

What a healthy TACOS looks like

There is no single good TACOS. It depends on two things: your margin and where the product is in its life.

Your margin sets the ceiling. Because margin after ads equals margin before ads minus TACOS, a product with 36.5% profit before ads loses money on the whole business above 36.5% TACOS. A product with 20% profit before ads hits zero at 20%. Know that number first.

The product's phase sets the expectation. A new product spends heavily to earn rank, then spend comes down as organic takes over. These are the ranges we work to:

A launch at 60% TACOS is not failing. An established product at 30% TACOS with flat sales probably is. Always place the product in its phase before you judge the number.

Here is what that profit phase looks like in practice. For one US brand we manage, monthly sales went from $90,326 to $182,575 while TACOS fell from 16.64% to 12.55%. Ad spend went up by about half. Sales doubled. That is ads working: more spend, more total revenue, and a smaller share of each dollar going to advertising. The full story is in our case studies.

How to calculate your TACOS

You need two numbers for the same date range.

1. Total ad spend. Add Sponsored Products, Sponsored Brands and Sponsored Display. Leaving out Brands and Display is the most common reason a TACOS looks better than it is.
2. Total sales. Use Ordered Product Sales from Business Reports in Seller Central, for the same products and the same dates.
3. Divide spend by sales. $10,800 ÷ $60,000 = 18%.
4. Do it per product, not just per account. An account TACOS of 12% can hide one product at 35% that is eating the profit of two others.

Use full weeks or months, not the last few days. Amazon keeps adding orders back to the click date for days afterward, so the most recent days always understate ad sales. Our free TACOS calculator does the arithmetic and shows your margin after ads in one step.

Using TACOS to set a budget

TACOS also gives you a simple ceiling for spend: TACOS target × revenue = spend limit. For the product above, a 15% target on $60,000 a month allows $9,000 of ad spend, about $300 a day. If you want to grow, raise revenue first or agree a higher TACOS limit for a set period on purpose. Do not let spend drift above the line by accident.

Mistakes we see

• Judging the account by ACOS alone. Every campaign looks fine, so nobody notices that ad share went from 40% to 60% and profit fell with it.
• Cutting a ranking campaign because its ACOS is high. If organic sales are rising behind it, TACOS is falling. Switch it off and organic often follows it down a few weeks later.
• Comparing a launch to a mature product. A 50% TACOS is normal in a ranking phase and a red flag on a product that has been selling for a year.
• Adding Brands and Display without checking TACOS. Add $3,000 of Sponsored Brands sales at 30% ACOS to a $10,000 account running 10% TACOS and the account TACOS jumps to 14.6%, often with little real incremental profit.
• Looking only at account-level TACOS. One heavy-spending product, or an overstocked item being pushed hard, can hide inside a healthy-looking total. Report those separately.
• Celebrating a lower TACOS while total sales fall. A lower ratio on a smaller business can still mean less money in the bank.

What to do this week

1. Pull the last three full months of ad spend (all ad types) and Business Reports sales for your top products.
2. Work out ACOS, TACOS and ad share for each product, each month.
3. Find any product where ACOS is steady but ad share is rising. That is ad spend replacing organic sales.
4. For those products, check organic rank on the main keywords and how much you spend on your own brand terms.
5. Set a TACOS ceiling per product from its margin and its phase, and keep spend under it.

Want us to check yours?

Most of the accounts we audit have at least one product where ads are quietly replacing organic sales, and nobody has seen it because the ACOS looks fine. Across 25 live brands and more than $7.5M in client sales, it is one of the first things we look for.

Our free Profit Audit, normally $500 and free until 31 December 2026, works out ACOS, TACOS and true margin after ads for each of your products, and shows you where spend is buying sales you already had. If you would rather talk it through, book a free 30-minute call. You can also see how we run Amazon PPC management for brands at your size.