What is left after an order? A contribution calculator

Start with contribution, then consider profit

Order contribution is the revenue from an order less the variable costs associated with that order. The remainder is available to cover fixed costs and, after those costs, profit. A positive contribution does not establish that the whole business is profitable.

Use the calculator as an illustrative planning tool. Its output depends on the values you enter and the costs included. It is general business education, not personal financial advice, a tax calculation or a forecast of future earnings. Use actual invoices and account reports to replace assumptions as soon as they are available.

Collect the costs behind one order

Start with the amount the customer pays, including delivery revenue where applicable. Then identify product cost, supplier handling, outbound freight, packaging and transaction charges. Check the basis used for any percentage fee: a platform may charge on amounts beyond the item price.

Include an appropriate allowance for advertising, returns or other variable expenses in the fields provided. Where the calculator cannot represent a charge accurately, work it out separately and include it in a suitable cost input. Do not treat an omitted cost as zero simply because it is awkward to estimate.

• Use one currency and a consistent treatment of tax throughout.
• Check whether freight or handling is already included in the supplier price.
• Avoid counting the same expense in both a fee field and another cost field.

Read a simple illustrative example

Imagine an order brings in $50. The product costs $20, delivery costs $8, selling and payment charges total $3, and other variable costs total $4. These invented figures leave $15 of contribution: $50 minus $35. The contribution margin is 30%, calculated as $15 divided by $50.

These amounts are examples, not supplier quotes or typical marketplace fees. If you reduce that order's revenue by $5 while keeping all the example costs unchanged, contribution falls to $10. That is why a small-looking discount can have a larger effect on the amount left per order.

Compare a base case with a difficult order

Write down your starting figures before changing an input. Then change one input at a time. Try higher freight, a promotional discount, more advertising expense or a replacement shipment. Use observed costs where possible and label assumptions explicitly. The purpose is to see which uncertainties matter most.

A return allowance spreads an estimated cost across orders; it does not predict which customer will return an item. Early in a business, you may not have enough history for a stable estimate. Revisit that input as evidence develops and keep enough detail to understand how you arrived at it.

Take the next step outside the calculator

List the costs that continue even with no orders: subscriptions, insurance, premises and other overheads relevant to your business. Consider the value of your own time as well. Contribution per order is only one part of the decision about whether an offer is worthwhile.

Cash timing is a separate question. Supplier payments, refunds and advertising bills may fall due before sales funds become available. Keep a cash-flow plan alongside order calculations, and ask an accountant or suitable adviser about tax treatment and decisions specific to your circumstances.