Nine places skincare brands quietly lose margin on Amazon

When a skincare founder tells us Amazon is “working,” they almost always mean revenue is growing. When we open the account, net margin is usually somewhere between weak and invisible. The two numbers can move in opposite directions for years without anyone noticing, because Amazon reports revenue every hour and profit never.

These are the nine places we look first, in the order we look at them. Most brands have four or five of them running at once.

1. Advertising that is managed to spend, not to margin

Ad budgets get set as a percentage of last month’s sales and then defended. Nobody asks what each campaign returns after fees. On the US skincare brand we operate, advertising was running at roughly 24% of revenue. We rebuilt the structure around a target advertising cost of sales per product, cut what could not hit it, and finished 2025 at 8.5% with revenue still up. That single change moved net margin from about 45% to 60.87%.

2. Broad-match campaigns nobody has pruned

Auto and broad-match campaigns are useful for discovery and expensive as a permanent state. If a search term has spent money for 60 days without converting, it should be negated. We find beauty accounts paying for “serum” and “moisturiser” as bare keywords for years.

3. FBA storage on slow SKUs

Skincare has long tails: the second shade, the travel size, the bundle nobody ordered. Monthly storage plus aged-inventory surcharges on those units erodes the margin of the hero product that pays for them. Check inventory age every month and decide, per SKU, to liquidate, remove or reprice.

4. Unclaimed reimbursements

Lost inbound units, damaged returns, overcharged weights. Amazon owes most sellers money at any given moment and pays only when asked within the window. This is boring, recurring work with a measurable return, which is exactly why it gets skipped.

5. Returns you never see

Beauty returns are high because texture, scent and shade are personal. Every returned unit costs the sale, the shipping both ways and often the product itself, since opened skincare cannot be resold. Reading return reasons monthly and fixing the listing copy or imagery that set the wrong expectation is one of the highest-return tasks on the account.

6. Size-tier and dimensional weight errors

A jar measured wrongly at check-in pays the wrong fee on every unit until someone disputes it. Verify dimensions on every new ASIN and on any product whose fee changes unexpectedly.

7. Coupons and deals stacked on already-discounted products

A Subscribe & Save discount, a coupon and a Lightning Deal can all apply at once. The order shows as a sale. The margin shows as a loss. Model the stack before enabling each promotion.

8. Listing decay

Ranked listings lose images, get merged, lose A+ modules, or inherit a competitor’s attribute edit. Conversion drops slowly and ad spend rises to compensate. A weekly listing health check catches it before the ad budget does.

9. No contribution-margin view at all

The root cause behind the other eight. If the only report anyone reads is sales, the account is optimised for sales. Build one sheet: revenue, referral fee, FBA fee, storage, advertising, returns, cost of goods, net. Per SKU. Monthly. Everything above becomes visible the first time it is filled in.

That sheet is what our margin audit produces. It is also the first thing we build for every brand we operate.

Filed under Margin