# TACoS vs ACoS: What Each One Actually Measures

Canonical page: https://www.kuudo.com/guides/amazon-ads-tacos-metric/

TACoS vs ACoS: compare ad spend against total revenue or ad-attributed sales, understand each formula, and choose the metric for the decision.

Author: Thomas Spicer
Updated: Oct 19, 2026

## Summary

- ACOS (Advertising Cost of Sales) equals ad spend divided by attributed sales. It's the exact metric Amazon's Ads API automates budget rules on for Sponsored Products and Sponsored Display.
- TACoS (Total Advertising Cost of Sale) equals ad spend divided by total revenue, not the same ad-attributed Sales figure ACOS uses. Same spend number, a different, bigger denominator.
- Amazon can automatically raise a Sponsored Products or Sponsored Display campaign's budget when ACOS meets a threshold you set. There's no equivalent automated rule for TACoS, because TACoS needs revenue data that lives outside the ad account.
- Sponsored Brands automation runs on ROAS (Return on Advertising Spend) instead of ACOS. Same underlying spend-to-sales relationship, a different metric name and a different threshold direction.

TACoS vs ACoS is a comparison of denominators. ACOS (Advertising Cost of Sales) is the percent of attributed sales spent on advertising, calculated by dividing total spend by attributed sales. TACoS (Total Advertising Cost of Sale) is the same spend number divided by a different, bigger denominator: your total revenue across every channel, not the 14-day ad-attributed Sales figure ACOS uses.

The ACOS formula is Amazon's own definition, and the exact metric its Ads API automates budget rules on for Sponsored Products and Sponsored Display. A brand lead asked me on Slack: *"our ACOS looks fine on every campaign, so why does leadership keep asking about TACoS like something's wrong?"* ACOS and TACoS aren't the same question asked twice. They're two different questions that share a numerator.

A generic answer stops at "TACoS looks at total sales, ACOS doesn't," which is true and useless for deciding what to do about it. What changes the answer for a specific account is which of the two moved and why:

- **ACOS fine, TACoS climbing** usually means organic sales are softening, not that the campaigns got worse.
- **No per-campaign budget rule can see that**, because a per-campaign rule only ever reads that campaign's own attributed sales.

I asked [our agent](/features/ai-clients/) to pull both numbers side by side through the [Amazon Ads MCP](/features/amazon-ads-mcp/), grounded by [Amazon Agent Atlas](/features/agent-atlas/) against Amazon's own metric definitions, so the two figures get compared on purpose instead of getting noticed separately by two different people in two different meetings.

## ACOS has an exact formula, and Amazon automates budget decisions on it directly

Amazon's own documentation defines ACOS precisely: total spend divided by attributed sales, supported for Sponsored Products and Sponsored Display campaigns specifically. This isn't a community approximation — it's a named metric in Amazon's Ads API that a budget rule can reference directly by its `metricName`.

The agent reads the live rule contract through the Amazon Ads MCP and can set one up the same way Amazon's own documentation demonstrates it:

```json
{
  "budgetRulesDetails": [
    {
      "name": "SAMPLE_BUDGET_RULE_ACOS",
      "ruleType": "PERFORMANCE",
      "duration": {
        "dateRangeTypeRuleDuration": { "startDate": "20201121" }
      },
      "recurrence": { "type": "DAILY" },
      "budgetIncreaseBy": { "type": "PERCENT", "value": 10 },
      "performanceMeasureCondition": {
        "metricName": "ACOS",
        "threshold": 20,
        "comparisonOperator": "LESS_THAN_OR_EQUAL_TO"
      }
    }
  ]
}
```

That rule increases a Sponsored Products or Sponsored Display campaign's budget by 10% automatically the day its ACOS is at or below 20%, no manual check required.

> **The AI is shared. The moat is yours.**
> - **A threshold you set is worth nothing unattended.** A chat can explain what ACOS means. It can't watch your live campaigns and fire the rule the day the number crosses your threshold, because it has no connection to your ad account. The Amazon Ads MCP holds that connection, and Atlas confirms `ACOS` is the correct metric name for the ad type before the agent submits anything.

## TACoS asks the same question against a bigger number

ACOS's denominator, Amazon's "Sales" column, is explicitly scoped: the total product sales you've received on your ads within 14 days from the date your ad was clicked. That's ad-attributed revenue, inside a fixed window. TACoS keeps the same spend number as its numerator but swaps in total revenue across every channel, ad-attributed or not, as the denominator.

That's why the two can genuinely disagree. A product with strong organic sales can carry a mediocre ACOS on paper while its TACoS stays low, because ads are a small slice of a large total. A product losing organic traction can hold a perfectly healthy ACOS on every campaign while its TACoS climbs steadily, because ads are covering a growing share of a shrinking total. Neither number is wrong. They're measuring the same spend against two different totals.

Total revenue is the piece an ad account can't see on its own, since it lives in order and settlement data, not in ad reporting. The agent reads it through the [Selling Partner MCP](/features/amazon-selling-partner-mcp/) and computes TACoS against that figure directly, rather than approximating total revenue from ad-attributed sales alone, which would just recompute ACOS with extra steps.

> **The AI is shared. The moat is yours.**
> - **Total revenue lives outside the ad account, so nothing inside it can compute TACoS alone.** A chat can define TACoS. It can't read what a store actually sold last week, because that data sits in Seller Central and Vendor Central, not in the ads system. The Selling Partner MCP reads the real order and settlement figures, so TACoS is computed against actual revenue instead of an ad-side guess.

## Sponsored Brands has no ACOS option at all, automated or otherwise

ROAS, return on ad spend, is total product sales divided by total advertising spend, the mirror of ACOS's spend-divided-by-sales relationship, expressed as a multiplier instead of a percentage.

Amazon's performance-based rules documentation scopes each metric to specific ad types: ACOS, click-through rate, and conversion rate are available for Sponsored Products and Sponsored Display only. Sponsored Brands isn't offered ACOS, click-through rate, or conversion rate as a rule metric at all; its options are impression share, new-to-brand percentage, and ROAS, which is the one metric available across all three ad types.

The agent checks which metric a given ad type actually supports before it proposes a rule, rather than assuming ACOS is universal across every campaign type, which would produce a rule Amazon's API rejects outright.

> **The AI is shared. The moat is yours.**
> - **The metric name depends on the ad type, and getting it wrong doesn't just look sloppy.** A chat that recommends "set an ACOS rule on your Sponsored Brands campaign" is describing a rule the Ads API has no metric for. The agent reads the actual metric list for the ad type from Atlas before proposing anything, so the rule that gets submitted is one Amazon will accept.

## Efficiency ratios can be scoped, not just totaled

ACOS and TACoS aren't limited to whole-account totals. [Amazon Marketing Cloud](/features/amc/) queries define `ntb_ACOS`, a new-to-brand-scoped version: ad spend divided by new-to-brand sales only, multiplied by 100. It answers a narrower question than portfolio ACOS does: how efficiently is this campaign specifically acquiring first-time customers, separate from repeat buyers padding the overall number.

The agent pulls this scoped definition from the same Atlas-grounded corpus as the portfolio-level formula, rather than guessing that a segment-level metric follows the same math by assumption. Amazon Marketing Cloud's own query templates spell out `ntb_ACOS` explicitly, so the scoped ratio is retrieved, not inferred.

A campaign can carry a fine blended ACOS while its `ntb_ACOS` is considerably worse, if most of its attributed sales are repeat customers who would likely have bought anyway. That's a different finding than a bad blended ACOS, and it calls for a different fix: better targeting for acquisition, not a lower bid across the board.

## Amazon advertising ROI reads at two levels: ROAS for each campaign, TACoS for the business

To analyze Amazon advertising ROI, read it at both levels. Amazon's `ROAS` divides ad revenue by ad spend and, in Amazon's words, "tells you how much money you earn for every dollar you invest in advertising." That is a campaign's return on its own ad-attributed sales. TACoS is the business's view: the same spend against everything the store sold.

Neither one is profit. Return on investment in the accounting sense also subtracts what the product cost, and product cost isn't in the ad account. The [ACoS formula guide](/guides/rules-data-mode-router/) turns contribution margin into a break-even ACoS, the line where ad spend stops paying for itself.

Improving the return works on the same levels:

- **Spend less for the same sales.** Cut spend on searches that don't convert, and pay less on clicks less likely to convert. The [Amazon PPC guides](/guides/amazon-ads-strategy/) cover each lever.
- **Give more budget to what returns the most.** A performance-based budget rule raises a budget when ROAS or ACOS meets your threshold, measured over the previous 7 days for sellers and 14 for vendors. It only raises budgets, so a campaign that stops returning needs a person or an agent to cut it.
- **Measure what ads outside Amazon return.** Amazon Attribution shows how search, social, display, video and email ads drive shopping activity and sales on Amazon, which Amazon describes as understanding the ROI of that marketing.

> **The AI is shared. The moat is yours.**
> - **ROI needs numbers from two systems and one rule of yours.** A chat can define ROAS. It can't set a campaign's ROAS beside what the store sold that week, because one number lives in the ad account and the other in Seller Central or Vendor Central. The agent reads ROAS through the Amazon Ads MCP and total revenue through the Selling Partner MCP for the same dates, holds both against the break-even point your [Skill](/features/skills/) keeps from margin, and proposes budget changes that go through your workspace policy before anything reaches Amazon.

## What happens next: set the budget rule on the metric each ad type supports and track TACoS separately {#what-happens-next}

The agent sets the automated budget rule on the metric the ad type actually supports, ACOS for Sponsored Products and Sponsored Display, ROAS for Sponsored Brands, and tracks TACoS separately as a recurring [Skill](/features/skills/) through the [Amazon Agent Data layer](/features/amazon-agent-flow/), since no budget rule can watch a number that lives outside the ad account.

When ACOS holds steady but TACoS starts climbing, that's the flag that the real problem isn't the campaign, it's the organic sales the campaign used to have help from. Two metrics, one spend number, and the gap between them is the actual signal. Everything else is a rounding argument.

*Next: the same performance-based rule mechanics applied to bids instead of budget, in [Amazon PPC Bidding Rules That Prevent Bid Thrash](/guides/rules-agent-bidding-rulebook/).*


## Frequently asked questions

### What does ACOS stand for and how is it calculated?

Advertising Cost of Sales (sometimes written ACoS). Amazon's own definition: the percent of attributed sales spent on advertising, calculated by dividing total spend by attributed sales. It's supported for Sponsored Products and Sponsored Display campaigns.

### What does TACoS stand for and how is it different from ACOS?

Total Advertising Cost of Sale. Same idea as ACOS, spend divided by sales, but the denominator is your total revenue across every channel, not just the 14-day ad-attributed Sales figure ACOS uses. A product can have a healthy ACOS and a rising TACoS if organic sales are falling.

### Can Amazon automatically adjust my budget based on ACOS?

Yes, upward, for Sponsored Products and Sponsored Display. A performance-based budget rule can specify ACOS as the metric name with a threshold and comparison operator, and it raises the daily budget by the percentage you set when the condition is met. Budget rules only increase budgets; when the condition isn't met, the campaign's normal daily budget applies.

### Is there an automated rule for TACoS the way there is for ACOS?

No. TACoS needs total revenue data that doesn't live inside the ad account, so Amazon's budget-rule API has no TACoS metric option. Tracking it requires pulling revenue from outside the ads system and comparing it yourself.

### Why does Sponsored Brands use ROAS instead of ACOS for automation?

Sponsored Brands has no ACOS option in Amazon's performance-based rules; its available metrics are impression share, new-to-brand percentage, and ROAS. ACOS, click-through rate, and conversion rate are scoped to Sponsored Products and Sponsored Display only. ROAS is the one metric available across all three ad types, expressed as a multiplier instead of ACOS's percentage.

### What is ntb_ACOS?

A new-to-brand-scoped version of ACOS used in Amazon Marketing Cloud queries: ad spend divided by new-to-brand sales only, times 100. It answers how efficiently a campaign is acquiring first-time customers specifically, separate from its overall ACOS.

### What's a reasonable ACOS threshold to automate on?

Amazon's own documented example rule increases Sponsored Products or Sponsored Display budget by 10% when ACOS is at or below 20%. That's an example threshold from Amazon's API guide, not a universal target; the right number depends on your margin structure.


## Sources

- [Performance-based rules](https://advertising.amazon.com/API/docs/en-us/guides/rules/budget-rules/performance-based)

- [Performance metrics](https://advertising.amazon.com/help/GG44RFW942U9F6F5)

- [Advertised product report for Sponsored Products](https://advertising.amazon.com/help/GYNVHW8R4QPYUS9H)

- [Understand budget rules](https://advertising.amazon.com/help/GNSMLANWNF344YBE)

- [Amazon Attribution](https://advertising.amazon.com/solutions/products/amazon-attribution)

- [Category benchmark (CBR) report for Sponsored Brands](https://advertising.amazon.com/help/G4XZ889CJ8D3NTXY)