ACoS is advertising spend divided by the revenue those adverts produced. TACoS is advertising spend divided by your total revenue, ad-driven and organic combined. ACoS answers “is this campaign efficient?” TACoS answers “is this business getting healthier?” Those are different questions, and a brand can score well on the first while quietly failing the second.
That’s the whole distinction. What follows is the part almost nobody publishes: what happens when you put the two numbers together.
The formulas
ACoS = (Ad spend ÷ Ad revenue) × 100
TACoS = (Ad spend ÷ Total revenue) × 100
Same numerator. Different denominator. TACoS is always the lower of the two, unless you have no organic sales at all, in which case they’re identical, and that’s a diagnosis in itself.
The number both metrics are hiding
Divide TACoS by ACoS and the ad spend cancels out. What you’re left with is the share of your revenue that came from advertising:
Ad-attributed share of revenue = TACoS ÷ ACoS
Organic share of revenue = 1 − (TACoS ÷ ACoS)
Two numbers you already have, one division, and you get the figure that describes your real position on Amazon.
Work an example. ACoS 20%, TACoS 18%. Those look like perfectly respectable numbers on a dashboard. Divide them: 18 ÷ 20 = 0.9. Ninety per cent of your revenue is ad-attributed. You have almost no organic business. Pause advertising on Monday and the account is gone by Friday.
Now a different account. ACoS 25%, TACoS 5%. The ACoS is worse: five points higher, the kind of number that gets flagged in a weekly review. But 5 ÷ 25 = 0.2, so only 20% of revenue is paid and 80% is organic. That’s a brand with a real position. It could switch its adverts off for a fortnight and survive.
The account with the worse ACoS is the far better business. If you manage to ACoS alone, you would optimise the second account towards looking like the first.
Why ACoS on its own misleads
ACoS is a campaign metric doing a job it was never built for.
It can only see the revenue Amazon attributes to the click. It cannot see the shopper who saw your Sponsored Product on Tuesday, didn’t click, searched your brand on Thursday and bought organically. It cannot see the rank you built by advertising into a term for six weeks. And it cannot see revenue shrinking, because a shrinking business can post a beautiful ACoS right up until the last order.
That’s the trap. Cut spend on anything above target and ACoS improves immediately. You have removed the least efficient spend, so of course the average looks better. What you may also have removed is the spend holding your organic position on your best terms. The ACoS improvement shows up this week. The rank decay shows up in six.
TACoS catches that, because the denominator includes the organic revenue you just undermined.
What each combination means
Read the two metrics as a pair, over 60 to 90 days. Single weeks are noise.
| ACoS | TACoS | What’s happening | What to do |
|---|---|---|---|
| Flat or rising | Falling | Organic revenue is growing faster than ad spend. Advertising is buying rank, and the rank is paying. | Keep going. This is the state you want. |
| Falling | Falling | Efficiency and organic both improving. | Nothing. Consider spending more. |
| Rising | Rising | Either a deliberate launch push, or losing efficiency and volume together. | Check ad share. Rising with high organic share is investment; rising with high paid share is a problem. |
| Falling | Rising | Adverts look more efficient while total revenue shrinks. Organic is collapsing underneath. | Stop. Diagnose rank before touching bids. |
That bottom row is the dangerous one, because every signal a weekly review looks at is green. ACoS improving. Cost per click down. Someone gets credit for efficiency. Meanwhile the business is contracting and the adverts are simply taking a larger share of a smaller pie.
If you check one thing after reading this, check whether your TACoS has risen over the last quarter while your ACoS fell.
What is a good TACoS?
Here are the ranges the industry quotes:
| Stage | TACoS commonly cited |
|---|---|
| Launch, 0–6 months | 15–25% |
| Growth, 6–18 months | 10–20% |
| Mature, 18+ months | 5–10% |
| Category leader | 3–7% |
Now the caveat, because it matters more than the table. These are not research figures. They’re industry estimates repeated between agency blogs, and the sources publishing them generally say so if you read closely. Nobody has run a study across a representative sample of Amazon accounts and published category-level TACoS distributions. The numbers are a sanity check, not a target.
The same applies to the ACoS benchmarks in circulation. Sponsored Products sit at 15–25%, Sponsored Brands at 20–35%, Sponsored Display at 25–40%, with category CPCs ranging from about $0.50 in books to $6.00 on competitive supplement terms. Directionally useful. Not something to manage a P&L against.
Two accounts in the same category with the same TACoS can be in completely different health, because TACoS says nothing about margin. A 10% TACoS on a product with a 45% gross margin is comfortable. The same 10% on a 22% margin product is most of your profit.
What to manage to instead
Your own trend. Where was TACoS 90 days ago, and which direction has it moved? That comparison tells you more than any benchmark, because it holds category, margin and price constant.
Your break-even ACoS. Your gross margin before advertising is the ceiling on what a campaign can spend and still make money. Below it you profit, above it you lose money on every order. This is the number a campaign should be judged against, and it’s specific to your product rather than your industry. Working it out properly is covered here.
Ad share of revenue. The TACoS ÷ ACoS figure from earlier. Track it monthly. A number falling over two quarters means organic is compounding. A number climbing means you’re becoming a paid-traffic business whether or not that was the plan.
When rising TACoS is fine
Rising TACoS during a launch isn’t a failure, it’s the point.
New products have no organic history, so the denominator is small and almost entirely paid. TACoS of 25–30% in the first weeks is normal. You’re buying velocity and reviews, and the return arrives later as organic rank you didn’t have to pay for.
What matters is the shape of the curve after that. TACoS should trend down over the following two to three months as organic sales accumulate. If it’s still at launch levels six months on, the adverts aren’t converting into rank, and the problem is upstream: the listing isn’t converting well enough for Amazon to reward it, or the terms you’re buying aren’t the terms shoppers actually use.
A launch has an exit. Perpetually high TACoS is not a launch, it’s a subsidy.
A worked month
An account doing £100,000 a month, spending £12,000 on adverts, with £48,000 of that revenue attributed to advertising.
- ACoS = 12,000 ÷ 48,000 = 25%
- TACoS = 12,000 ÷ 100,000 = 12%
- Ad share = 12 ÷ 25 = 48% of revenue is paid
- Organic share = 52%
That’s a reasonable position. Just over half the business stands on its own.
Ninety days later, revenue is £92,000, spend is £11,000, ad-attributed revenue is £55,000.
- ACoS = 11,000 ÷ 55,000 = 20%, improved by five points
- TACoS = 11,000 ÷ 92,000 = 12%, unchanged
- Ad share = 12 ÷ 20 = 60% of revenue is paid
- Organic share = 40%
Every dashboard says this quarter went well. ACoS improved, spend came down, TACoS held. But revenue fell 8%, organic revenue fell from £52,000 to £37,000 (down nearly 29%), and the paid share of the business grew by twelve points.
The adverts got more efficient. The business got weaker. Only the ad-share calculation makes that visible, and it takes one division.
The short version
ACoS tells you whether a campaign is efficient. TACoS tells you whether the business is growing. Divide TACoS by ACoS and you get the share of revenue you’re renting rather than owning, which is the number that decides whether you have an asset or a habit.
Track all three monthly. Judge campaigns against your break-even ACoS, not against a benchmark you found on a blog — and recalculate it after every fee change, since FBA fees moved again in January 2026 and dimension errors quietly inflate them further. And treat any quarter where ACoS improved while TACoS rose as a problem to investigate rather than a result to celebrate.
FAQ
What is the difference between ACoS and TACoS? ACoS divides ad spend by ad-attributed revenue and measures campaign efficiency. TACoS divides the same ad spend by total revenue, including organic sales, and measures how dependent the whole business is on advertising. A campaign can post a strong ACoS while TACoS shows the business is shrinking.
What is the TACoS formula? TACoS = (Total ad spend ÷ Total revenue) × 100. Total revenue includes both ad-attributed and organic sales for the same period.
What is a good TACoS on Amazon? Commonly quoted ranges are 15–25% at launch, 10–20% in growth, and 5–10% for established products. These are industry estimates rather than published research, and they ignore margin entirely. Your own 90-day trend and your break-even ACoS are more reliable guides.
Can TACoS be higher than ACoS? No, unless every sale you make is ad-attributed, in which case they’re equal. TACoS uses a larger denominator, so it’s always lower than ACoS when organic sales exist. If the two numbers are close together, you have almost no organic business.
Why is my ACoS falling but my sales dropping? Usually because you cut spend on terms that were holding organic rank. The efficiency gain is immediate and the rank loss is delayed, so the two rarely get connected. Rising TACoS alongside falling ACoS is the signature of this pattern.
How often should I check TACoS? Monthly, against a 60 to 90 day trend. Weekly TACoS is mostly noise: promotions, competitor activity and stock levels move it enough to generate false signals.
Sami Sultan runs Ecom Enable, an Amazon growth partner for DTC brands. Figures and benchmark ranges verified 27 August 2026. Where a number is an industry estimate rather than published research, this article says so.
Sources: Keywords.am on TACoS formulas and stage benchmarks; Clickstera’s 2026 Amazon advertising benchmarks by category. Both state their benchmark ranges are operational estimates rather than third-party research.