the rule
The most you can take off before an order loses money is what that order leaves you, as a share of the price. If a $100 order leaves $33 after the product, the fees, the shipping and the ad that won it, 33 percent off is break even. On a $100 item, every dollar the ad costs takes one point off that.
Two things move that line in Black Friday week: what the ad costs you per order, and who the order comes from. You can know both before the 27th.
the surprise in the ad numbers
Do ads really cost more on Black Friday?
Views do. Orders, not always. Lebesgue looked at $22.6 million of Meta spend from its biggest spenders, September to November 2025. The median brand paid 59 percent more per 1,000 views in Black Friday week than in September, and 84 percent more on Black Friday itself. In the same week its cost per purchase fell 20 percent, because purchases per click rose 48 percent (Lebesgue).
Lebesgue is careful about why: stronger offers, readier buyers and a different mix of traffic may all play a part, and the purchases are the ones Meta counted. So the honest reading is this: the price of attention goes up, and whether the price of an order goes up depends on your offer and your store. Your own number from last November is the one to use.
the table
How much does a discounted order leave?
One example product. The numbers below are made up to show the steps, not taken from any store. A $100 item that costs $35 to make and pack, and $12 in payment fees and shipping. On a normal week it takes about $20 of ads to win an order, so it leaves $33.
| Discount | Ads cheaper per order (down 20%, $16) | Ads the same ($20) | Ad prices passed straight on (up 59%, $31.80) | From your list (no ad cost) |
|---|---|---|---|---|
| None | $37.00 | $33.00 | $21.20 | $53.00 |
| 10% off | $27.00 | $23.00 | $11.20 | $43.00 |
| 20% off | $17.00 | $13.00 | $1.20 | $33.00 |
| 30% off | $7.00 | $3.00 | loses $8.80 | $23.00 |
| 40% off | loses $3.00 | loses $7.00 | loses $18.80 | $13.00 |
| Biggest discount before a loss | 37% | 33% | 21% | 53% |
Read the third column first. If an order costs what the higher prices suggest, 20 percent off leaves $1.20, and you need more than 27 discounted orders to earn what one full price order earned in October. Now read the first column: the same 20 percent leaves $17, and that is a sale worth running. Same discount, same product. The only difference is what an order costs you in ads, so that is the number to find first.
Then read the last column. The same 20 percent, sent to people already on your list, still leaves $33, because nobody paid for the click.
when it gets expensive
When do ad prices peak around Black Friday?
Not in the same week on Meta and Google.
| 2025 season | Google, price per click, against September |
|---|---|
| Early to mid November | up 12% to 16% |
| Black Friday week | up 7% (Thanksgiving week) |
| Cyber Monday week | up 27% |
| The week after | up 28% |
| The dear stretch | Cyber Monday week and the week after |
Google: 113 stores' accounts against their September average (SmartSites).
On Meta, the expensive week is the famous one. In Lebesgue's numbers the climb started in the week of 10 November, about two and a half weeks before Black Friday (Lebesgue). An early sale for new customers buys its views before the steepest part.
On Google, it runs later. Thanksgiving week was only 7 percent above September. Cyber Monday week and the week after were 27 to 28 percent up, and Cyber Monday was the most expensive single day of the year for a click (SmartSites). If most of your orders come from Google, the week to watch is the one after the famous one.
the orders nobody paid for
Should everyone get the same discount?
I would not. The orders that cost you nothing in ads can take the deeper cut. The orders you paid for usually cannot. In the example, 30 percent off for your list still leaves $23 an order. The same 30 percent for a stranger who came through an ad leaves $7 at best, and loses money if the ad prices pass straight on.
Shopify does this without an app. In a discount's Eligibility section, choose Customer segments or Specific customers instead of All customers (Shopify Help Center). One catch worth knowing: a segment discount works only for customers who already have a profile in your store, so a first time buyer is not in the segment until their first order is complete (Shopify Help Center). Here, that is the point. It also means the public offer is the only one a stranger sees.
three checks
What should I check in Shopify before the 27th?
Cost per item on everything in the sale. Shopify leaves sales with no cost recorded out of its gross profit, so a big sale can look better than it was. How to check it.
The Eligibility line on every code. A list only code set to All customers is the costliest typo of the season.
Sales channels, then Agentic. Shopify now lists eligible products in AI channels such as ChatGPT, Microsoft Copilot and Google AI Mode, and it is on by default for eligible stores (Shopify Help Center). ChatGPT sends the buyer to your own checkout (Shopify Help Center). Worth a look before the sale, so you know where your products are showing up.
decide it, then check it
How will I know if the sale was worth it?
Write it down before it starts, with the number you expect to hold. "20 percent off for the list, 10 percent for everyone else, 23 to 30 November. Profit per order stays above $10." Then in December, look at that number, not at total sales, which will look wonderful either way.
two moves
Find last November's ads per order.
In your ad account, take last November's spend and divide it by the orders it brought in, first orders if you can split them. Put that in the calculator instead of the example.
Split the codes before the 23rd.
A deeper one for your list, set to a customer segment, and a modest one for everyone else. Then read the Eligibility line on each one twice.
straight answers
The questions founders ask about this.
How much discount can I afford on Black Friday?
Up to what one order leaves you as a share of the price, after product cost, fees, shipping and the ads that won it. If a $100 order leaves $33, 33 percent off is break even.
Are Facebook ads more expensive on Black Friday?
The price of views is. In Lebesgue's 2025 data the median brand paid 59 percent more per 1,000 views in Black Friday week than in September, and 84 percent more on the day. Its cost per purchase fell 20 percent in the same week, because more clicks turned into orders.
When are Google Ads clicks most expensive around Black Friday?
In SmartSites' 2025 data, Cyber Monday week and the week after cost 27 to 28 percent more per click than September, and Cyber Monday was the most expensive day of the year. Thanksgiving week was 7 percent up.
Can I give my email list a bigger discount in Shopify?
Yes. In the discount's Eligibility section, choose Customer segments or Specific customers. Segment discounts work only for customers who already have a profile in your store.