Black Friday 2026: the discount that sells more and keeps less.

Black Friday falls on 27 November this year and Cyber Monday on 30 November. Most stores decide the discount by looking at what competitors are doing and picking a round number. The number that should decide it is the one the banner never shows: what each order keeps after the discount.

One product, worked through

Take a €49 product sold in the Netherlands, where 21% VAT sits inside the price. The store pays €14 for it, the payment fee comes to about €1.20 on the full price, the parcel costs €4.50 to send, and ads cost €12 per order. These are example figures — the method is what matters.

At full price: €49 ÷ 1.21 = €40.50 kept after VAT. Less goods €14, fee €1.20 and shipping €4.50 leaves €20.80 before ads. Less €12 of ads: €8.80 profit per order.

Now take 30% off. The customer pays €34.30. The VAT shrinks with the price, and so does the percentage part of the payment fee — but the goods cost the same, the parcel costs the same, and an order still costs whatever the ads cost to win.

At 30% off: €34.30 ÷ 1.21 = €28.35 kept after VAT. Less goods €14, fee €0.84 and shipping €4.50 leaves €9.01 before ads. Less €12 of ads: −€2.99. The order now loses money.

How many more orders it needs to stand still

Before ads, the discounted order keeps €9.01 against €20.80 at full price. To earn the same contribution the store needs 2.31 times as many orders — and that is before a single extra euro of advertising, which on Black Friday usually costs more per order, not less.

The arithmetic: €20.80 ÷ €9.01 = 2.31. Redo it with your own figures: (full-price contribution) ÷ (discounted contribution) is the volume multiple the discount has to deliver just to break even.

The return on ad spend it needs

Break-even ROAS is the price divided by what an order keeps before ads: below it, the ads cost more than the order leaves. At full price this product breaks even at 2.36×. At 30% off it needs 3.81× — and ad platforms report ROAS on the price paid, VAT included, so a campaign showing 3× can be losing money on every sale.

Full price: €49 ÷ €20.80 = 2.36×. At 30% off: €34.30 ÷ €9.01 = 3.81×.

Four rules for this year’s discount

• Work out the break-even ROAS per product at the discount you plan, before the campaign — not after the first week of spend.
• Discount the products that have the margin to give. A flat sitewide percentage hits the thin-margin products hardest.
• Test it. Since 2 October Shopify’s Rollouts can run a discount on part of your traffic against your current offer — but read the result in money kept per visitor, not in conversion rate.
• Watch the free-shipping threshold. A discount that pulls baskets under it makes the store pay for the parcel on top.

Profflow shows the break-even ROAS for every product from its own costs, and the "Before you list it" check on the Stock & costs screen runs this exact sum for a price you type — with your VAT rate, your shipping and your real ad cost per order already filled in.