How much you really make on each sale in your online store

You sell a product for €49.90 and it feels as if you have made €49.90. You haven't. Out of that amount come the VAT (IVA), what the product cost you, the shipping, the payment fee and whatever you spent on ads to bring that customer in. What is left after all that is what you really earn on the sale.

This article goes through it piece by piece, with an example order. At the end you will see what stays out of the sum and why: income tax (IRPF) and the self-employed social security contribution.

1. The VAT is not yours

When you sell to a consumer in Spain, the price the customer pays has the VAT inside it. The law requires the seller to charge the tax to the customer and then pay it over to the tax authority (article 88 of the Spanish VAT Act). The money passes through your account, but it was never yours.

So the real income from a sale is the taxable base: the price without VAT. These are the rates that apply in Spain:

• 21%, the standard rate (article 90 of the VAT Act).
• 10% and 4%, the reduced rates, only for the goods and services the law lists (article 91).

The Spanish Tax Agency (AEAT) sums it up like this: «El tipo general de IVA es el 21%. Los tipos reducidos vigentes son el 10% y el 4%» (the standard rate is 21%; the reduced rates in force are 10% and 4%). Its page has a document for each year listing which products take each rate. If you are not sure which one applies to you, check there before you set your prices.

To get the base from a VAT-inclusive price, divide the price by 1 plus the rate. At 21%: €49.90 ÷ 1.21 = €41.24. The VAT is the difference: €8.66.

2. What the product cost you

This is what you paid for the unit you sold: the purchase from your supplier, or the materials and making if you produce it yourself. Count only the share that belongs to that unit. If you buy a batch of 100, spread the cost over the 100.

A common mistake is to deduct the same cost twice: once unit by unit and again as the supplier's whole invoice at the end of the month. Pick one method and stick to it.

3. The shipping you pay

Even if you charge the customer for delivery, what you pay the carrier is a cost. And if you offer free shipping, you pay all of it. Look at the carrier's invoice for that order, not a rough average: weight, destination and service level change the price a lot.

4. The payment gateway fee

The company that takes the card or other payment for you keeps part of each charge. Most often it is a percentage of the amount charged plus a fixed fee per order. The percentage is usually applied to what the customer pays, that is, the price including VAT rather than the base; check this in your own terms.

Every gateway and every plan has its own terms, and they change. Don't rely on figures you read elsewhere: find yours in your contract or on the pricing page of your account, and check against a statement that what you are charged matches.

5. Ads

If you pay for advertising to sell, part of that spend belongs to each order. The simplest way to share it out is to divide what you spent on ads in a period by the orders in that period. It is not exact, because not every order comes from an ad, but it is far better than leaving it out. An order that looks profitable without ads can lose money once you add them.

The example: a €49.90 order

These figures are an example. They are not real prices or fees from any company. All costs are shown without VAT.

• Price paid by the customer: €49.90, including 21% VAT.
• Product cost: €15.00.
• Shipping you pay: €4.50.
• Payment gateway (example): 1.5% of the charge plus €0.25 per order.
• Share of ad spend for this order: €6.00.

Item	Calculation	Amount
Price including VAT	What the customer pays	€49.90
VAT (21%)	€49.90 − €41.24	€8.66
Sale without VAT (base)	€49.90 ÷ 1.21	€41.24
Product cost		− €15.00
Shipping you pay		− €4.50
Gateway fee	€49.90 × 1.5% = €0.75, plus €0.25	− €1.00
Ads		− €6.00
What you keep	€41.24 − €15.00 − €4.50 − €1.00 − €6.00	€14.74
Margin	€14.74 ÷ €41.24	35.7%

Of the €49.90 the customer paid, you keep €14.74. That is less than a third of the price. And the fixed costs of the business (software, the store subscription, office supplies) still have to come out, shared across all the month's sales.

If you want to run this sum with your own numbers, use the order profit calculator.

6. Returns

When a customer sends a product back and you refund them, that sale disappears in full or in part. The VAT Act says that when a transaction is cancelled in full or in part, or the price changes after it took place, the taxable base is adjusted by the corresponding amount (article 80.Dos).

To correct the VAT you issue a corrective invoice (factura rectificativa). The Spanish invoicing regulation makes it compulsory in the cases covered by article 80 of the VAT Act (article 15.2) and asks for it to be issued once you know what happened (article 15.3). The corrective invoice is a new invoice that identifies the one it corrects (article 15.4).

For your margin, a return usually costs more than the lost sale: you already paid the outbound shipping, sometimes you pay for the return too, the gateway fee is not always refunded and the product may come back damaged. If you have a lot of returns, track them separately and take them off your monthly numbers.

7. Income tax: Form 130 is an advance

If you are under the direct assessment method (estimación directa), you file Form 130 every quarter. It is a payment «a cuenta» (on account) of income tax (article 109.1 of the IRPF Regulation): an advance, not the final tax. It is 20% of your net profit accumulated from the first day of the year to the end of the quarter, minus what was due in the earlier quarters of the same year (article 110.1.a). We walk through an example in the article on Form 130.

The final reckoning happens in the annual income tax return. That is where the tax for the whole year is worked out and what you paid in advance with Form 130 is taken off.

That is why it makes little sense to deduct income tax order by order. It is better to set aside part of what you keep each month and ask your accountant how much it should be in your case.

8. The self-employed contribution

Your social security contribution also depends on what you earn. It works in bands of monthly net earnings: depending on which band yours fall into, you choose a contribution base between a minimum and a maximum. For 2026 the bands and their bases are set out in Order PJC/297/2026, which publishes a «tabla general» (general table) and a «tabla reducida» (reduced table).

Like income tax, the contribution is not deducted from each order. It is a cost for you as a self-employed person, not for each sale. What helps is knowing how much the business leaves you and, separately, how much goes on the contribution and how much to set aside for income tax.

Summary

1. Take out the VAT: your income is the price without VAT.
2. Deduct the product cost, once.
3. Deduct the shipping you pay, using the real invoice.
4. Deduct the gateway fee, using the terms in your contract.
5. Deduct each order's share of ad spend.
6. Deduct returns and correct their VAT with a corrective invoice.
7. Set aside, separately, income tax and the self-employed contribution.

To try it with your own numbers, start with the free calculator, or try Plentia free for 14 days, no card needed.

Sources

• Agencia Tributaria · Tipos impositivos de IVA (VAT rates, in Spanish) · checked on 26/09/2026
• BOE · Ley 37/1992, VAT Act (articles 80, 88, 90 and 91) · checked on 26/09/2026
• BOE · Real Decreto 1619/2012, invoicing regulation (article 15) · checked on 26/09/2026
• BOE · Real Decreto 439/2007, IRPF Regulation (articles 109 and 110) · checked on 26/09/2026
• BOE · Orden PJC/297/2026: 2026 contribution bases and rates (includes the self-employed) · checked on 26/09/2026