How to Price a Bundle: The Margin Math Behind 3-Packs
Most founders pick a bundle discount because it sounds right. Price it from profit per order instead, and a 3-pack at 10% off can out-earn the same pack at 20% off by $559 a month.
I used to price bundles the way most founders do. I'd pick a number that sounded generous. 20% off. Done.
It took me an embarrassing amount of time to notice that the number I picked had nothing to do with my costs.
Here's how to price a bundle properly. Start from the profit you make on one single order, after product cost, shipping and payment fees. Work out what the bundle saves you per order, which is mostly the boxes you don't have to ship. Then set the bundle price so it earns more than the same units would earn as separate orders. The discount is the output of that math. It's never the starting point.
Get that order right and a 3-pack becomes one of the cheapest order value lifts in your store. Get it backwards and you're paying customers to buy what they were going to buy anyway.
Why is a round discount the wrong way to price a bundle?
Because 10%, 15% and 20% are numbers your brain likes. Your margin doesn't care about them.
A round number feels like a bundle pricing strategy. It's a guess with a percent sign on it. And it ignores the one thing that makes bundles profitable in the first place: one box carries three products. The fulfillment cost that used to hit you three times now hits you once.
That saving is real money. It's also finite. Discount past it and the bundle starts eating margin instead of spending savings.
Shopify lists "pass along discounts to your customers" as one of the benefits of bundling (Shopify Help Center). Fair. The question is which discount you're passing along. The one the box paid for, or the one your margin paid for?
A bundle discount funded by the box you didn't ship is a lift. A bundle discount funded by your margin is a leak with nicer packaging.
What does a single order really earn you?
Let's run the math on a store like this, a hypothetical. One product: a 12-ounce bag of whole-bean coffee at $32.
- Product cost: $9 a bag
- Shipping and packaging: $7 per order
- Payment fee: 3% of the order (an assumption; check your own rate on Shopify's pricing page, since it varies by plan and country)
One bag, one order: $32 minus $9 minus $7 minus $0.96 in fees. That's $15.04 profit per order, a 47.0% margin.
Write that number down. Every bundle price gets judged against it. If you haven't split your costs this way before, the contribution margin breakdown walks through every line.
How much discount can a 3-pack afford?
Three bags list at $96. The pack ships in one box, which costs a little more: say $9 instead of $7. Product cost is $27.
Here's the math at the three discounts founders always argue about.
| 3-pack | Price | Product cost | Shipping | Fees (3%) | Profit per order | Margin |
|---|---|---|---|---|---|---|
| Single bag (for reference) | $32.00 | $9.00 | $7.00 | $0.96 | $15.04 | 47.0% |
| 10% off | $86.40 | $27.00 | $9.00 | $2.59 | $47.81 | 55.3% |
| 15% off | $81.60 | $27.00 | $9.00 | $2.45 | $43.15 | 52.9% |
| 20% off | $76.80 | $27.00 | $9.00 | $2.30 | $38.50 | 50.1% |
Every row beats the single bag. Even at 20% off, the pack earns $38.50 per order, and its margin percent is higher than a single bag's. You'd have to go past about 45% off before the 3-pack earned less than one bag.
So 20% is fine, right?
Not so fast. That's the wrong comparison.
Price minus product cost, shipping and a 3% payment fee. Three separate orders is the bar the 3-pack has to beat.
Where does the 3-pack beat single units, and where does it lose?
Your coffee buyers don't buy once. The good ones come back. And a customer who would have bought three bags across three orders earns you 3 x $15.04 = $45.12.
That's the real bar.
At 10% off, the pack earns $47.81. It wins by $2.69, because the $12 of shipping you saved (three $7 boxes versus one $9 box) more than paid for the $9.60 discount.
At 15% off, it earns $43.15. It loses $1.97 against three separate orders.
At 20% off, it earns $38.50. It loses $6.62.
Here's the math on the break-even. Solve for the price where the pack's profit equals $45.12, and you get $83.63. That's a discount of about 12.9%. The $12 of shipping funds roughly 12.5 points of it, and the smaller card fee on one order covers the rest.
Below your break-even discount, the bundle spends savings. Above it, the bundle spends margin. That line is the whole job.
So who is the bundle for? That decides everything.
- If the 3-pack mostly pulls in buyers who'd only ever take one bag, deeper discounts still win, since $38.50 beats $15.04 by a mile.
- If it mostly pulls your loyal re-buyers forward, stay at or under your break-even, because they'd have paid you $45.12 anyway.
Most stores have both. So price for the re-buyer and let the single-bag buyer enjoy the deal. That's the safe side of the line.
What does that do to the whole store?
Run it across a month, same hypothetical. 10,000 visitors. 2.0% conversion rate. 200 orders.
Before the bundle: average order value $32. Revenue per visitor is 2.0% x $32 = $0.64. On 10,000 visitors that's $6,400 in revenue and $3,008 in profit.
Now say 30% of buyers take the 3-pack at 10% off (an assumption, held the same at every discount so the comparison stays clean). That's 140 single orders and 60 packs. Revenue: $4,480 plus $5,184 is $9,664. Average order value climbs to $48.32. Revenue per visitor goes to 2.0% x $48.32 = $0.97. Profit: $2,105.60 plus $2,868.48 is $4,974.
Same 60 packs at 20% off? Revenue drops to $9,088 and profit to $4,415.
Same traffic. Same take rate. $559 a month in profit gone, just from picking the bigger round number.
Does a bigger bundle discount sell more bundles?
Sometimes. Less often than you'd think.
Judy Harris and Edward Blair tested this in the Journal of Product & Brand Management. Bundle discounts raised bundle choice when shoppers were prompted to look at item prices, like when those prices were prominent or the purchase felt unfamiliar. Otherwise, the discount "had little effect on choice" (Harris and Blair, 2012).
Read that again with your product page open. If the per-bag price isn't on the page, your extra 10 points of discount may be doing almost nothing. If it is, a modest discount gets noticed.
So show it. "$28.80 a bag, normally $32" beats "Save 10%" because it hands the buyer the comparison the research says drives the choice.
This is also why I'm wary of copying benchmark tables. One bundle app blog suggests a 10% to 25% range and a 35% to 45% margin floor (BOGOS), but cites no source for either. Those can be useful starting guesses. Your own break-even is the number that matters, and it takes four minutes to find.
If you're stacking tiers (one, two, three bags), the same math applies per tier. The tiered pricing breakdown and the post on whether quantity breaks raise average order value cover how the ladder should step.
How is AI changing bundle pricing?
The math above is one product. Your catalog might have 40. That's where founders give up and go back to "20% off everything."
AI removes that excuse. Shopify says its Sidekick assistant can "write and run its own code to forecast, compare, or summarize your store data" (Shopify Help Center). Ask it for your repeat-purchase rate by product and how many orders had two or more of the same item. That tells you who your bundle is really for.
Then run the margin check on every pack at once.
Here's the thing, though. A bundle can only multiply what the page already sells. Look at one Amazon product we moved to Shopify: it sold for $17.95 on Amazon and netted $3.83 a sale. On Shopify, average order value went to $101.38 and net profit per sale to $48.27, after paying for ads and inventory. See the full case study numbers. Real client numbers, not typical results, and not a promise of what your store will do. The bigger order came from a page that sold it at a price that held margin, not from a deeper discount.
If you're new to building the offer itself, start with how to use product bundles on Shopify, then compare the bundle against a BOGO or percent-off offer.
What to do next
Open a spreadsheet. Put your best seller's price, product cost, shipping per order and fee rate in four cells. Calculate one order's profit, then three separate orders, then the 3-pack at 10%, 15% and 20%. Find the break-even. If your current bundle discount sits above it, drop it to the break-even this week and show the per-unit price on the page. Watch profit per order for 30 days.
When you're ready for the full order value lineup, the average order value playbook ranks every lever in order.
Book Your Profit Audit
A bundle priced from margin raises the order your product page already earns. On a free profit audit we'll show you where your revenue per visitor is leaking before the bundle ever shows up, and how to rebuild a high-converting product sales page in less than 15 minutes.
Or go here to check it out → revenueflows.ai
P.S. The box you don't ship pays for the discount. Anything past that, your margin pays for. Price the bundle where the box stops paying.
Frequently asked questions
How do you price a bundle?
Start with the profit on one single order after product cost, shipping and payment fees. Add up what the bundle saves you per order, mostly the boxes you don't ship. Then set the bundle price so its profit beats the same units sold as separate orders, and show the per-unit saving on the page.
What is a good bundle discount percentage?
There's no universal number. In a hypothetical coffee store, the shipping saved on a 3-pack funded about 12.9% off before the pack started earning less than three separate orders. Work out your own break-even first, then pick a discount at or below it. For many stores that lands somewhere around 10% to 15%.
Should a bundle be cheaper than buying items separately?
Usually yes, because shoppers expect a saving. But Harris and Blair found bundle discounts mostly sway choice when shoppers are actually comparing item prices. So make the per-unit price visible, and you can win with a smaller discount than you think.
How do I calculate bundle profit margin?
Take the bundle price, subtract the cost of every unit inside it, the shipping and packaging for that one box, and the payment fee on the bundle price. Divide what's left by the bundle price. Compare that profit in dollars against a single order, and against the same units bought in separate orders.
Can AI help price a bundle?
Yes, for the arithmetic and the catalog work. Shopify says Sidekick can write and run code to forecast, compare or summarize your store data, and a bundle calculator can check every pack against the single unit in minutes. The judgment call, who the bundle is for, is still yours.