Add invoice tax and regulatory fees to campaign spend, then compare the true cost with your KDP royalty margin.
Last reviewed: 19 August 2026
Enter the actual percentages from your Amazon Ads invoice. Tax treatment varies by advertiser.
| Metric | Result | Meaning |
|---|---|---|
| Console ACOS | — | Campaign spend ÷ attributed sales |
| Total amount paid | — | Spend + regulatory fee + tax |
| Effective ACOS | — | Total amount paid ÷ attributed sales |
| Break-even ACOS | — | Royalty per sale ÷ list price |
| Net ad contribution | — | Estimated royalties − total amount paid |
Amazon says advertising fees can be subject to VAT or GST for electronically supplied services. Its sponsored ads terms also state that advertising fees are exclusive of applicable taxes. If the Ads Console shows $100 of campaign spend but your invoice adds 20% VAT, you paid $120. Your effective ACOS is therefore higher than the campaign-only ACOS.
Use campaign spend and attributed sales from the same reporting period.
Enter the VAT/GST and any regulatory advertising fee actually charged.
Effective ACOS must stay below your royalty-based break-even ACOS for direct ad sales to contribute profit.
Assume Amazon Ads Console reports $100 spend and $250 attributed sales, with no regulatory fee. Console ACOS is 40% in both cases.
| Invoice tax | Total paid | Effective ACOS |
|---|---|---|
| 10% GST | $110 | 44% |
| 20% VAT | $120 | 48% |
These examples explain the calculation only. The rate and charges on your actual Amazon Ads invoice control your result.
Does Amazon charge VAT or GST on ads?
It may, depending on your billing country, tax registration and local rules for electronically supplied services.
Why is effective ACOS higher than Console ACOS?
Console ACOS can exclude invoice-level taxes and fees. Effective ACOS uses the total amount you actually pay.
Should I include VAT if I can reclaim it?
For cash-flow planning, calculate the invoice amount first. If the tax is recoverable, run a second scenario with a 0% tax rate and confirm treatment with your accountant.
Does this replace my invoice?
No. It is an estimate; your Amazon Ads invoice and local tax rules are authoritative.
Amazon Ads — VAT/GST on electronically supplied services
Amazon Ads — regulatory advertising fees
KDP Ads Break-Even Calculator — include TACOS, organic sales and KENP income.
KDP Ads Budget Calculator — estimate clicks, maximum CPC and test spend.
Estimates only. Verify every charge against your Amazon Ads invoice. This tool is not tax or financial advice.