Types of Profit Margin
Profitability is measured at multiple levels in your P&L. Each tells a different story:
| Margin Type | Formula | What It Measures |
|---|---|---|
| Gross Margin | (Revenue − COGS) ÷ Revenue | Product profitability before operating costs |
| Contribution Margin | (Revenue − All Variable Costs) ÷ Revenue | Per-sale profitability including ads, shipping, returns |
| Operating Margin | (Revenue − COGS − OpEx) ÷ Revenue | Business profitability before interest and tax |
| Net Margin | Net Profit ÷ Revenue | Bottom-line profitability after all costs |
Use gross margin for per-product decisions and advertising targets. Use net margin to assess overall business health and compare periods.
E-commerce Margin Benchmarks by Category
Margin expectations vary enormously by product category. A 25% gross margin that is mediocre for apparel is excellent for consumer electronics. Use the table below to benchmark your performance:
| Category | Gross Margin | Net Margin (Healthy) | Notes |
|---|---|---|---|
| Consumer Electronics | 20–35% | 3–8% | High competition, price sensitive |
| Apparel & Footwear | 45–65% | 8–15% | High returns offset strong gross margin |
| Health & Beauty | 50–70% | 10–20% | Strong brand loyalty reduces ad dependency |
| Home & Garden | 35–55% | 7–14% | Higher AOV offsets logistics costs |
| Sports & Outdoor | 35–50% | 6–12% | Seasonal demand adds complexity |
| Toys & Games | 40–60% | 7–13% | Heavily seasonal, high return rate |
| Food & Grocery | 20–40% | 2–8% | Tight margins, high fulfilment complexity |
| Pet Supplies | 35–55% | 8–15% | High repeat purchase potential |
Why E-commerce Margins Are Being Squeezed
The structural pressures on e-commerce margins have intensified significantly since 2020. Understanding them is the first step to countering them.
Rising Advertising Costs
Google Shopping CPCs have increased by 20–40% in most categories since 2021, driven by more advertisers competing for the same clicks. Brands that haven't adjusted their ROAS targets to reflect rising CPC are spending proportionally more on ads without improving profitability.
Increasing Return Rates
Customer expectations around free returns have pushed average return rates higher. Apparel now averages 25–35% online returns. The fully-loaded cost of a return (inbound postage, handling, inspection, restocking, potential markdown) is typically £5–£15 per item — often exceeding the net profit on the original sale.
Carrier & Fulfilment Cost Increases
Carrier rates have risen 8–15% annually for several consecutive years. 3PL fulfilment rates have followed. For brands offering free shipping, this cost increase falls entirely on their margin.
Platform Fee Increases
Shopify, Amazon, and other platforms have increased fees for merchants. Amazon FBA fees have risen significantly for many category sizes. These directly compress the margin available after COGS.
The Compounding Effect
Each of these pressures individually might be manageable. Combined, they create a compounding effect: a brand that's seen ad costs rise 25%, returns increase 5 percentage points, and carrier costs rise 12% has likely lost 5–8 net margin points since 2021 — without changing a single product price or supplier cost.
Strategies to Improve Gross Margin
Gross margin is driven by the gap between your selling price and your COGS. You have two levers:
Reduce COGS
- Negotiate volume discounts with existing suppliers
- Optimise packaging to reduce materials cost and dimensional weight
- Rationalise SKU range to concentrate volume on fewer, better-priced products
- Review inbound freight contracts — spot rate vs. forwarder contract rates
Increase Prices
- Test price increases on products with strong demand and low price elasticity
- Bundle products to increase AOV and improve margin mix
- Add premium variants with higher price points
- Review products priced below market rate — particularly private label items
Strategies to Improve Net Margin
Net margin improvement requires addressing operating costs as well as COGS. The highest-impact areas for most e-commerce brands:
Advertising Efficiency
Set ROAS targets based on individual product margins rather than a blanket account target. Pause or restrict products with insufficient margin to support advertising. This reduces ad spend waste without reducing revenue from profitable products.
Reduce Return Rates
Investing in better product descriptions, size guides, comparison tables, and customer photography typically reduces return rates by 3–8 percentage points. At a £6 average return handling cost, a 5-point reduction in return rate saves £0.30 per unit sold — compounding across high-volume SKUs.
Shipping Strategy Optimisation
Set free shipping thresholds at an AOV that ensures the incremental margin from the free-shipping uplift outweighs the shipping cost subsidy. Many brands set thresholds too low.
Fixed Cost Leverage
Growing revenue faster than fixed costs (warehousing, software, staff) improves net margin through operating leverage. Focus growth investment on scalable channels before expanding fixed cost base.
How Google Ads Performance Affects Net Margin
For brands driving significant revenue through Google Shopping, ad efficiency is the single biggest controllable lever on net margin. A 20% improvement in ROAS doesn't just improve campaign performance — it flows directly to net profit.
ROAS IMPACT ON NET MARGIN
Brand with £1M annual revenue, 50% gross margin (£500K gross profit)
Current Google Ads spend: 18% of revenue = £180,000 | Net margin: ~4%
—
If ROAS improves by 20% (spend drops to 15% of revenue = £150,000):
Ad cost saving: £30,000 | Net margin improvement: 3 percentage points
Net margin: 4% → 7% — a 75% improvement in net profit from a 20% ROAS improvement
Per-SKU ROAS Targets Are Essential
A blanket ROAS target treats a 70% margin product the same as a 25% margin product. GROW Platform calculates the minimum viable ROAS for each product individually and targets bids accordingly — so high-margin products attract aggressive bids and low-margin products are protected from spend that would erode their profit.
Per-SKU Profitability: Where the Real Work Happens
Aggregate margin figures conceal the reality of your catalogue. A 45% average gross margin can be made up of 30 products with 60%+ margins and 20 products running at 15% — the latter consuming ad budget that generates revenue but destroys net margin.
Build a per-SKU profitability view with at minimum: selling price, COGS (landed cost), gross margin %, average selling frequency (units/month), and your estimated ad cost per unit sold. This reveals which products are genuine profit generators and which are margin parasites.
Action on Low-Margin Products
For products with gross margin below 25%: (1) Can you increase the price? (2) Can you reduce COGS through supplier negotiation? (3) Should you remove them from Google Shopping and sell through organic or direct channels only? (4) Should you discontinue them entirely? Each option is preferable to continuing to advertise them at a loss.
Frequently Asked Questions
What is a good gross margin for e-commerce?
It varies significantly by category. Consumer electronics: 20–35%. Apparel: 45–65%. Health & beauty: 50–70%. Home & garden: 35–55%. If your gross margin is below 30% in any category, you will struggle to cover advertising, shipping, and operating costs and remain profitable.
What is a good net profit margin for e-commerce?
A net margin of 5–15% is typical for well-run e-commerce businesses. Below 5% leaves very little buffer against cost increases or sales slowdowns. Above 15% is excellent and usually indicates either a high-margin category, strong brand power, or exceptionally lean operations.
Why are e-commerce margins shrinking?
The main pressures are: rising Google and Meta CPC costs, increasing return rates, higher carrier and fulfilment costs, growing customer acquisition costs, and marketplace fee increases. Many brands have seen net margins compress by 3–5 percentage points over 2022–2025.
How does Google Ads spend affect my net margin?
Google Ads spend is typically 8–20% of revenue for e-commerce brands. Every percentage point reduction in ad cost as a percentage of revenue — through better ROAS — flows directly to net margin. A 20% ROAS improvement for a brand spending 18% of revenue on ads improves net margin by ~3 percentage points.
What is the fastest way to improve e-commerce profit margins?
Three high-impact levers: (1) Improve ROAS targets per product based on actual COGS — stop spending on low-margin products. (2) Audit return rates by product and address root causes. (3) Review shipping strategy — free shipping thresholds set too low can erode 3–5% of net margin.
Next Steps
Run a per-SKU margin analysis on your top 50 products by revenue. Identify the 10 products with the lowest gross margin that are currently receiving Google Shopping budget. For each one, calculate whether the campaign is generating a positive contribution margin — or whether you're spending to subsidise sales that lose money once all variable costs are counted.
Margin-Driven Bidding, Automated
GROW Platform stores your full cost stack per product and automatically calculates the profitable ROAS target for every SKU. Your Google Shopping campaigns bid based on real per-product economics — protecting your net margin on every click. Create an account →
