Transaction Unit Economics: 30% of Sales Lose Money (Identify & Eliminate)
Online retailer order: SGD 50 price, SGD 30 COGS (GROSS SGD 20). Minus shipping SGD 5, payment fee SGD 1, customer support contact SGD 2, return (10% rate, 50% cost) = 5% × SGD 15 = SGD 0.75. Net profit: SGD 20 - SGD 5 - SGD 1 - SGD 2 - SGD 0.75 = SGD 11.25 (22.5% margin). Looks good. But outlier: low-volume SKU (A/B testing), 20% return rate (quality issue), higher support cost (assembly question). Actual net: SGD 50 - SGD 30 - SGD 5 - SGD 1 - SGD 4 (support) - SGD 5 (returns) = SGD 5 (10% margin). Or: negative margin if customer demands refund (50% chance for low-quality item).
- What Kills Unit Economics?
- The Hidden Cost Structure
- Identifying Losing Transactions
- AskBiz Unit Economics Dashboard
- Building the Full-Cost Transaction Model
What Kills Unit Economics?#
(1) Shipping: heavy/bulky items eat 10-20% margin. (2) Returns: high return rate (20%+) can swing profitable to loss-making. (3) Payment processing: international payments 3-5% fee. (4) Support cost: new/complex product requires customer calls/emails. (5) Refunds/disputes: chargeback rate >1% kills profitability.
The Hidden Cost Structure#
Simplified: Price - COGS = gross profit. Detailed: Price - COGS - Shipping - Payment Fee - Support - Returns = net profit. Most businesses track first 2, ignore last 3. Missing 15-25% of cost = incorrectly measure profitability.
Identifying Losing Transactions#
Rank all products by net margin (full calculation). Expect: top 20% very profitable (30%+), middle 50% moderate (10-20%), bottom 30% low/loss-making (<5% or negative). Bottom 30% are dragging down overall margin. Action: discontinue or price appropriately (raise price 10-20% if elastic allows).
AskBiz Unit Economics Dashboard#
Calculates full margin per SKU including all hidden costs. "Top 20 SKUs by volume: avg 28% net margin (keep selling). Bottom 20 SKUs: avg -2% net margin (losing money on each sale). Recommendation: (1) discontinue 10 SKUs (lowest margin), (2) price increase 10% on 10 others (reduce volume loss if inelastic, improves margin). Projected impact: +5% blended margin = SGD 12.5K additional annual profit."
Building the Full-Cost Transaction Model#
Start from gross margin (price − COGS) and add five deduction lines: shipping cost allocated per unit, payment processing fee (as a % of price), a per-order support cost (total support hours × hourly cost ÷ orders for that SKU), a returns cost (return rate × (product cost + reverse shipping + restocking labour)), and any promotional discount applied at checkout. The formula: net unit profit = price − COGS − shipping − payment fee − allocated support cost − (return rate × return cost) − discount. Most SMBs stop at gross margin because the other five lines require pulling data from different systems — POS for price/COGS, courier invoices for shipping, payment gateway statements for fees, a helpdesk log for support time, and a returns log. The work is in assembling this once; after that, it's a repeatable monthly calculation.
Worked Example: The SKU That Looked Profitable But Wasn't#
A Singapore online furniture retailer had a flat-pack desk priced at SGD 180 with SGD 90 COGS — a healthy-looking 50% gross margin. Adding the full cost model: shipping (bulky item, courier surcharge) SGD 35, payment fee at 2.9% = SGD 5.22, support cost allocated per order (this SKU generated 3x the average number of assembly-help tickets) SGD 12, and a 18% return rate at SGD 60 cost per return (product damage in transit plus restocking) = 0.18 × 60 = SGD 10.80. Net unit profit: SGD 180 − 90 − 35 − 5.22 − 12 − 10.80 = SGD 26.98, a 15% net margin — still positive, but barely a third of the 50% gross margin the SKU appeared to carry on a simple P&L. A second desk model with a 35% return rate due to a packaging defect showed a net margin of −4%, meaning every sale was a loss once full costs were included — and this SKU was the one that got pulled from the catalogue.
Common Mistakes When Calculating Unit Economics#
The most common mistake is allocating support and returns costs evenly across all SKUs instead of by actual usage — a product prone to confusion or damage should carry more of the support and returns cost than one that never generates a ticket, and averaging hides exactly the SKUs you need to find. The second mistake is using a return rate from too small a sample; a new SKU with 3 orders and 1 return looks like a 33% return rate but may settle to 8% once volume grows, so wait for at least 30-50 orders before trusting a return-rate input. The third is treating a negative-margin SKU as an automatic discontinue without checking whether it drives basket size — a loss-making desk that reliably gets bundled with profitable accessories may still be worth keeping if the bundle-level economics are positive. AskBiz calculates full-cost unit economics automatically from POS, payment, and returns data so this analysis runs monthly without a manual data pull each time.
People also ask
Should I always discontinue low-margin items?
Not if they have strategic value: (1) customer acquisition (loss leader), (2) bundling (sell unprofitable item with profitable), (3) seasonal (profitable 3 months/year). But: set time limit (6-month trial), measure ROI, discontinue if not justified.
How do I improve unprofitable unit economics?
Reduce costs: negotiate lower shipping, reduce returns (improve quality), negotiate payment fees. Or: increase price and accept volume loss if inelastic. Or: bundle with profitable items (hidden price increase). Or: discontinue.
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Analyze Unit Economics (Eliminate Losing Transactions)
AskBiz calculates net margin per SKU including all costs (shipping, fees, support, returns). Identifies unprofitable items. Recommends pricing or discontinuation. Try free.
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