What is ACoS on Amazon?

Formula, category benchmarks, and how to read ACoS alongside your net margin

Definition

What it is

ACoS (Advertising Cost of Sale) is the ratio of Amazon advertising spend to advertising-attributed revenue, expressed as a percentage. If you spend $100 on Sponsored Products ads and those ads generate $500 in attributed sales, your ACoS is 20%. ACoS is the primary efficiency metric for Amazon PPC campaigns — a lower ACoS means you are generating more revenue per dollar of ad spend.

Formula

ACoS Formula

Formula

ACoS (%) = (Ad Spend ÷ Ad-Attributed Revenue) × 100

ACoS is the inverse of ROAS (Return on Ad Spend): ACoS = 1 ÷ ROAS × 100. A 25% ACoS = 4× ROAS. Your break-even ACoS is your gross margin percentage — if your margin is 30%, an ACoS above 30% means you are losing money on every ad-attributed sale. Target ACoS should be set below break-even ACoS to maintain profitability.

Business impact

Why it matters

ACoS determines whether your advertising is profitable, but it must be read alongside net margin to be meaningful. A 15% ACoS on a product with 18% net margin is barely profitable after ad spend. The same 15% ACoS on a product with 45% net margin is excellent. Many sellers optimise for a low ACoS without checking whether the underlying product margin supports it — leading to revenue growth with declining profitability.

The challenge

How most teams track this today

ACoS is available directly in Amazon Advertising Console per campaign and per ASIN. However, the Advertising Console does not show ACoS alongside FBA fees and net margin in the same view. Combining ad performance data with product profitability data requires joining the advertising report with the orders and fee data — typically done in a spreadsheet or BI tool.

Run it on your data

Calculate this automatically with Taptic Data

Connect your Amazon Seller Central account and Taptic generates this calculation from plain English against your actual data — no Excel exports, no manual joins. The SQL runs against your real schema, your real tables, your real numbers.

SQL query for Amazon net margin by SKU — including ad spend context →Connect Amazon Seller Central →Try Free — $29.99/mo

FAQ

Common questions

What is a good ACoS on Amazon?

It depends on your product margin. As a starting point: ACoS should be below your gross margin percentage to be profitable on ad-attributed sales. For most FBA categories, a 15–25% ACoS is considered healthy. Highly competitive categories (supplements, electronics) often see 30–40% ACoS during launch phases, which is acceptable if the organic ranking improvement justifies the short-term spend.

What is the difference between ACoS and TACoS?

ACoS (Advertising Cost of Sale) divides ad spend by ad-attributed revenue only. TACoS (Total Advertising Cost of Sale) divides ad spend by total revenue — organic plus ad-attributed. TACoS gives a truer picture of advertising efficiency because it accounts for the halo effect of ads on organic sales. A product with 25% ACoS but 8% TACoS is using ads very efficiently to drive organic growth.

How do I find my break-even ACoS?

Break-even ACoS = your gross margin percentage. If you sell a product for $30 with $8 COGS, $4.50 referral fee, and $3.50 FBA fee, your gross margin is ($30 − $8 − $4.50 − $3.50) ÷ $30 = 46.7%. Your break-even ACoS is 46.7%. Any ACoS below this means ad-attributed sales are profitable; above it means you are subsidising those sales.

Does Taptic import Amazon advertising data?

Taptic connects to Amazon Seller Central via the SP-API. The SP-API provides access to advertising report data through the Advertising API, which is a separate integration. For ACoS tracking alongside margin data, the most common approach in Taptic is to use the net margin query as a profitability baseline and track ACoS separately in the Amazon Advertising Console.

Analytics hub

All Amazon queries, use cases, and SQL examples in one place.

Amazon Analytics hub — queries, use cases, and SQL examples →

Stop calculating this in spreadsheets

Connect Amazon Seller Central to Taptic Data and run this calculation automatically from plain English — against your real data, on a schedule, delivered to your team.

Start Free — $29.99/mo Try the Live Demo