Amazon marketing · Answer
The short answer
Amazon charges no fee to use its advertising platform and nothing for impressions. You pay only when somebody clicks, and you never pay more than the bid you set. What you actually pay per click is decided by an auction against the other sellers bidding on that keyword, which in India commonly lands between ₹8 and ₹20 outside the cheapest categories.
Sellers often expect a management charge or a monthly minimum for Amazon advertising. There is neither. The advertising console comes with your seller account, and the only money that moves is what you spend on clicks.
That is also why an agency fee and an ad budget are two completely separate lines. If a proposal blurs them together, ask for them split out before you sign anything.
Amazon runs a second-price style auction. Setting a ₹40 bid does not mean paying ₹40. It means ₹40 is your ceiling, and you typically pay a small increment above whatever the next competitor was willing to pay.
This is the part that makes bid panic counterproductive. Cutting a bid because the ceiling looks alarming often just loses you the placement without having saved anything, because you were never paying the ceiling.
Relevance and conversion rate. Amazon has no reason to keep showing an ad nobody clicks or a listing nobody buys from, so a listing that converts well tends to win placements more cheaply than a listing that does not.
This is the same reason listing work beats bid work. Cost per click and conversion rate move your advertising cost of sale identically, and only one of them is free to improve.
Amazon's referral fee, which is a percentage of every sale and varies by category, will almost certainly cost you more over a year than your advertising does. It comes out of the same margin your ACoS target is calculated from.
Check your category's referral fee in Seller Central before you set an advertising target, because that fee is inside your break-even whether or not anyone included it.
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