How to Calculate Shopify Profit Per Order: Contribution Margin Made Simple

Revenue is the number every new store owner watches, and it is the one that misleads them most. A store can sell $20,000 a month and lose money on every order once shipping, payment fees, returns and ads are counted. The fix is to calculate profit per order, also called contribution margin. This guide shows you how, with a worked example and the formulas you need to set prices and ad budgets.

The contribution margin formula

Contribution margin per order = Order revenue − all variable costs of that order

Variable costs are anything that happens because the order happened:

Fixed costs such as your Shopify plan, apps, software and salaries are not included. They are covered by the total contribution from all orders.

Step 1: Calculate landed cost

Your supplier's unit price is not your product cost. Landed cost adds everything it takes to get the product into your warehouse.

Example: You order 500 units at $8.00 each.

The real cost is $10.70, not $8.00. Pricing from the supplier quote alone would have overstated your margin by more than 30%.

Warning: Tariffs and duty rates can change quickly. Recalculate landed cost on every new purchase order, not once a year.

Step 2: Build the order-level P&L

Take a typical order of one product priced at $39 with free shipping.

That 38% is what each order can spend on marketing and still break even.

Step 3: Calculate break-even ROAS

Break-even ROAS = 1 ÷ contribution margin before marketing (as a decimal)

1 ÷ 0.38 = 2.6

Every $1 of ad spend must produce at least $2.60 in revenue just to break even on that order. At a ROAS of 2.0, you lose about $4.59 per order. At 4.0, you earn about $5.16.

This table is the single most useful number set for deciding whether to scale an ad campaign.

Step 4: Factor in repeat purchases

A loss on the first order can still be a good investment if customers come back. If 30% of customers buy again within six months, and repeat orders arrive through email at almost no acquisition cost, the second order contributes nearly the full $14.91.

Simple lifetime contribution = first-order contribution + (repeat rate × repeat orders × repeat contribution)

With a first-order contribution of $1.91 at 3.0 ROAS, a 30% repeat rate and 2 repeat orders on average among repeaters:

$1.91 + (0.30 × 2 × $14.91) = $10.86 per customer

Be honest about your repeat rate. Use real data after a few months, not hopes at launch.

Step 5: Turn contribution into monthly profit

Contribution per order only becomes profit after it covers your fixed costs. Add up everything that does not change with order volume: Shopify plan, apps, email platform, design tools, bookkeeping, insurance, and any salary you pay yourself or a team.

Orders needed to break even = monthly fixed costs ÷ contribution per order after marketing

Using the example above at a 3.0 ROAS ($1.91 per order after ads) and $1,500 of monthly fixed costs:

$1,500 ÷ $1.91 = about 785 orders a month

That is a lot of orders for a new store. Now raise the average order to $52 by bundling a $13 accessory that costs $3 landed. Product, packaging and payment costs rise a little, but shipping and pick-and-pack barely move, and contribution after ads at the same ROAS climbs to roughly $5 to $6 per order. Break-even drops to under 300 orders. This is why experienced operators work on order value and margin before they work on traffic.

Tip: Keep a simple spreadsheet with one row per product: price, landed cost, packaging, fulfillment, average shipping, fees, returns allowance and contribution. Update it whenever a supplier, carrier or price changes.

How to improve thin margins

Raise average order value

• Bundles ("buy two, save 10%")
• Free shipping thresholds set above your average order
• Post-purchase upsells

If average order value rises from $39 to $52 with a second unit, shipping and packaging barely change, and contribution jumps.

Lower variable costs

• Negotiate supplier price at higher volume
• Right-size packaging to cut dimensional weight charges
• Compare carriers and 3PL rates annually
• Reduce returns with better photos, size charts and descriptions

Price for the margin you need

If your contribution before marketing is under about 30%, paid ads become very hard to run profitably. Test a higher price. Many new store owners underprice because they compare themselves with marketplaces.

Profit-per-order checklist

• ☐ Landed cost calculated for every product
• ☐ Packaging and fulfillment cost per order measured
• ☐ Actual average shipping cost tracked monthly
• ☐ Processing fee and returns allowance included
• ☐ Contribution margin before marketing calculated per product
• ☐ Break-even ROAS known for each product and campaign
• ☐ Repeat purchase rate tracked after 90 days
• ☐ Review all numbers monthly

Mistakes to avoid

• Using supplier price instead of landed cost
• Offering free shipping without raising product prices
• Judging ads by platform-reported ROAS without checking actual orders
• Ignoring returns and discounts in the math
• Scaling ad spend before contribution margin is positive

Your next step

Knowing your profit per order changes every decision you make, from pricing to ad budgets. Starting a Shopify E-commerce Store by Omer Muneer Qazi covers product validation, sourcing, landed cost, unit economics, Shopify Payments, sales tax, shipping, marketing and paid ads, with worksheets that turn revenue into real profit.