ACoS, TACoS and Profit: The Amazon Metrics That Actually Matter

Key takeaways: ACoS is ad spend divided by ad-attributed sales; it tells you how efficient the advertising is. TACoS is ad spend divided by total sales; it tells you how dependent the business is on advertising. Neither tells you whether you made money. Profit per unit, after Amazon fees, cost of goods, returns and advertising, is the number that decides whether an ACoS is good or bad. Use ACoS to manage campaigns week to week, TACoS to judge the strategy month to month, and profit per ASIN to decide what to scale, hold, fix or retire.

Three numbers, three different questions

Sellers argue about ACoS as if it were the score of the game. It is not. It is one of three numbers that each answer a different question, and the mistakes people make with Amazon advertising usually come from asking one number a question it cannot answer.

ACoS answers: how efficient is the advertising? Spend $1,000 on ads, get $4,000 of ad-attributed sales, and ACoS is 25%. It is measured per campaign, per keyword, per ASIN, and it moves week to week. It is the number you manage bids and search terms against.

TACoS answers: how much of the business depends on ads? Spend the same $1,000 and the ASIN's total sales, organic plus paid, are $10,000, so TACoS is 10%. It measures the relationship between advertising and the whole business. It moves slowly and it is the number you judge strategy against.

Profit answers: did any of this make money? Take the price, subtract Amazon's referral fee, the FBA fee, the landed cost of the unit, the cost of returns and the advertising cost per unit sold, and you have profit per unit. Multiply by units and you have profit per ASIN. This is the number that decides whether a 25% ACoS is excellent or ruinous.

Understanding ACoS, TACoS and profit as three separate questions is the first step. The second is knowing which one to look at when.

ACoS: what it is good for and what it hides

ACoS is the fastest-moving of the three, which is why it is the one to use for weekly campaign decisions. A keyword whose ACoS has been above its target for two weeks needs a look. A placement whose ACoS is double the campaign average has a modifier set too high. A search term with spend and no sales is waste.

But ACoS hides three things.

It hides organic sales. A campaign that runs at 40% ACoS while lifting the ASIN's organic rank may be the most profitable thing in the account. Cut it to hit a 25% target and the organic sales that came with the rank go too. This is the single most common way sellers damage a healthy account: managing to an ACoS target without looking at what happened to total sales.

It hides the margin. A 25% ACoS is strong for a product with 45% margin before advertising and a loss for a product with 20% margin. The number means nothing without the break-even figure next to it.

It hides the stage. A product in month one of launch is supposed to run a high ACoS; it is buying data, rank and reviews. A mature product with the same ACoS has a problem. Reporting both in one blended figure makes the launch look like a failure and the mature product look better than it is.

If your ACoS is above where you want it and you are not sure why, Amazon ACoS Too High? What to Fix First (and What to Leave Alone) walks through the order of checks. The short version: conversion rate first, wasted search terms second, placements third, bids last.

Break-even ACoS: the line that gives ACoS meaning

Break-even ACoS is the ACoS at which an ad-attributed sale makes zero profit. It is simply your margin before advertising, expressed as a percentage of price.

Work it out per ASIN. Start with the selling price. Subtract Amazon's referral fee (a percentage that varies by category), the FBA fulfillment fee for the unit's size tier, the landed cost of goods, and an allowance for returns and storage. What is left, divided by the price, is your break-even ACoS.

A worked example, with round numbers for illustration: a product sells at $40. Referral fee $6, FBA fee $7, landed cost $12, returns and storage allowance $2. Margin before advertising is $13, or 32.5% of price. Break-even ACoS is 32.5%. At 25% ACoS each ad sale earns $3 of profit; at 40% it loses $3.

Then set a target ACoS below break-even that leaves the profit you actually need. If you want to keep half the margin on ad-attributed sales, the target in the example is about 16%. If the product is in launch, the target is deliberately above break-even for a defined period. If it is a mature product whose ads mostly protect rank, the target can sit closer to break-even because the organic sales carry the profit.

Break-even ACoS changes when anything in the cost stack changes: a fee update, a price change, a new supplier, a rise in returns. Recalculate it whenever one of those moves, or at least quarterly.

TACoS: the number that judges the strategy

TACoS, sometimes written as total ACoS or ad spend as a share of total revenue, is the most useful single number for judging whether the advertising strategy is working over months.

It works because it captures the thing ACoS hides: the relationship between paid and organic. If ad spend stays flat and total sales grow because organic rank improved, TACoS falls. If ad spend grows and total sales grow with it in proportion, TACoS is flat and the business is scaling. If ad spend grows and total sales do not, TACoS rises and the ads are cannibalizing sales you would have made anyway or buying sales that stop when the ads stop.

Three patterns to read:

TACoS falling, sales flat or rising. The healthiest pattern. Organic is taking over. Keep doing what you are doing and consider whether spend can taper further.

TACoS flat, sales rising. Scaling. The ads are buying growth at a constant cost. Fine, as long as profit per unit holds and stock can keep up.

TACoS rising, sales flat or falling. The warning pattern. Either the ads are buying sales that were previously organic (check organic rank and the share of ad orders), or competition has pushed cost per click up, or the listing's conversion has fallen. Diagnose before cutting.

What is a good TACoS? It depends on category, margin and stage, so treat any single benchmark with caution. What is universally true is that a mature product's TACoS should be lower than its target ACoS, because organic sales dilute the ad cost, and it should trend down over time as rank consolidates. A product whose TACoS equals its ACoS has almost no organic sales, which is normal at launch and a problem after it.

For the strategy of deliberately bringing TACoS down, see How to Shift Amazon Sales from Paid to Organic (TACoS Control).

Profit per unit: the number that decides

ACoS and TACoS are both ratios. Neither is money. A product can have a beautiful 12% TACoS and lose money on every unit because the FBA fee ate the margin. Profit per unit is the number that ends the argument.

Build it per ASIN, per month, from the actual figures rather than estimates: units sold, average selling price after promotions, referral fees, FBA fees, storage fees, returns and their cost, cost of goods, and advertising spend attributed to the ASIN. Divide by units. The result is what each sale actually left in the business.

Then rank the catalog by total monthly profit, not by revenue. In most accounts the ranking is a surprise. The revenue leader is often not the profit leader, and one or two products that look busy are quietly losing money on every order. That ranking drives the decision that matters most: what to scale, what to hold, what to fix and what to retire.

• Scale the ASINs with healthy profit per unit, headroom in rank and stock to support it.
• Hold the ASINs that are profitable and stable where more spend would push ACoS past break-even.
• Fix the ASINs with thin profit and an identifiable cause: a fee that could drop with a packaging change, a return rate a listing fix could cut, a price that has not been tested.
• Retire or stop advertising the ASINs that cannot be made profitable at any ACoS. That is a product decision, not a PPC one.

Amazon Unit Economics: Finding the Margin That Can Fund Growth covers the unit economics build in detail, including where the margin usually leaks.

How the three fit together in practice

The rhythm we use: ACoS weekly, at keyword and campaign level, for the operational changes. TACoS monthly, per ASIN, to judge whether the strategy is working. Profit per unit monthly, per ASIN, to decide what the strategy should be next month.

What to put in the report

A useful Amazon report shows all three, at the level where each makes sense.

The last row matters more than it looks. A blended account ACoS that mixes a launch running at 60% with mature products running at 20% tells you nothing about either. Report launches separately, always. Amazon PPC Reporting: Weekly, Monthly and Quarterly Metrics sets out the fuller weekly, monthly and quarterly report.

Common mistakes with these metrics

Managing the account to a single ACoS target. Different products have different margins, stages and jobs. One target across all of them is wrong for most of them.

Cutting bids to lower ACoS and calling it a win. ACoS falls, spend falls, sales fall, rank slips, organic sales fall a month later. Check TACoS and total sales before celebrating a lower ACoS.

Ignoring TACoS because "it moves slowly". It moves slowly because it measures the thing that matters. A rising TACoS over three months is the earliest clear signal that the strategy, not just a bid, is wrong.

Never calculating break-even. Without it, "good ACoS" is a guess. It takes twenty minutes per ASIN and changes every decision after it.

Using revenue to decide what to scale. Revenue is what Amazon shows you. Profit is what you keep. Scaling a high-revenue, thin-margin product with more ad spend is the fastest way to grow a business that loses money.

Blending launches into the account figures. The launch looks like a disaster and the mature products look better than they are. Neither gets the right decision.

How WeSpark works with these numbers

Every account we run has a break-even ACoS per ASIN and a target set below it that fits the product's stage and margin. The weekly report shows ACoS by keyword and campaign and what we changed because of it. The monthly report shows TACoS and ad share of orders per ASIN, with launches separated out, and profit per unit after fees, cost of goods, returns and advertising. That profit ranking drives the scale, hold, fix or retire call for each product, which we make with you on the monthly call.

D5ACoS above targetadvertising cost back inside your band within about 30 days, without cutting the terms that sell.

D6Total ad cost creeping up (TACoS)a falling ad-cost share, with launches reported separately so they do not distort the picture.

C8Increasing profit, not just salesprofit per unit for every ASIN, and a clear call on what to scale, maintain, fix or retire.