Short answer: Facebook ads for a Shopify store cost whatever you decide to spend, because Meta lets you set the budget, so the real question is how much you have to spend before you know if it's working, and whether each sale comes in under what you can afford to pay for it. That second number comes from your margins, not from Meta, and it's the first thing I'd want to know about any store. Do that math first, then fix the setup (tracking, catalog, creative), and only then worry about the budget.
So here's how I'd think about it if it were my store, in the order I'd actually do it.
What Facebook ads cost a Shopify store
There's no price list. You pay for the auction: Meta charges you for impressions or clicks, and the price moves with your industry, your audience, the season (try buying ads the week before Black Friday, it's a whole thing) and, more than anything, how good your ads are.
What you can control is the budget, and the budget has one job early on: buy enough data for Meta to learn who buys from you. If you spread $20 a day across five campaigns, none of them gets enough purchases to learn anything, and you end up judging ads on a handful of sales, which is basically flipping a coin and calling it strategy.
Here's where I'd start. Depending on what your product costs, I'd run roughly $100 a day across 5 ads in different formats, all aimed at your ideal customer. That's enough data to see whether engagement is healthy and to start learning which formats your buyers respond to.
That changes if you sell something that isn't aimed at consumers, or anything that costs more than about $250. In those cases I'd spend roughly the product's price per day, with a goal of averaging a 3x return over two weeks.
The break-even math to do first
Before you spend a dollar, work out the most you can pay for a sale and still make money. It's one line of math:
Break-even ROAS = 1 ÷ your gross margin
ROAS is return on ad spend: revenue from ads divided by what you spent on them. Gross margin here should be what's left of an order after product cost, shipping, payment fees and any discount, not the margin on the sticker price.
Say your average order is $60 and you keep $24 of it after all of that. That's a 40% margin, so your break-even ROAS is 1 ÷ 0.40 = 2.5. Every $100 in ads has to bring in $250 in sales just to break even. At 2.5 you're even. At 2 you're paying Meta for the privilege of shipping boxes. At 4 you've got a business.
Two things change the answer, and you should know which one you're playing:
- Repeat buyers. If customers reorder (supplements, coffee, skincare, anything consumable), you can afford to lose a little on the first order, because the second and third orders are where the profit is. That only works if you actually know your repeat rate, not if you're hoping for one.
- Average order value. Bundles, a free-shipping threshold and a decent upsell all raise what each sale is worth, which lowers the ROAS you need. Sometimes the cheapest fix for bad ads is a better offer.
If the math only works at a ROAS you've never seen, no campaign setting is going to save it. Fix the offer or the margins first.
The setup that decides whether it works
Here's the thing about Meta right now: the algorithm decides who sees your ads mostly from the ads themselves and from the purchase data you send back. Your creative is basically your targeting, and your tracking is how Meta knows what "worked" means. So the setup matters more than the campaign settings.
1. Connect Shopify to Meta properly
Use Shopify's Facebook & Instagram app (the Meta sales channel) to connect your store, your pixel and your catalog. In the app's data sharing settings, choose the highest level you're comfortable with, which turns on the Conversions API. That sends purchases to Meta from Shopify's servers, not just from the shopper's browser, and browser tracking alone can miss sales because of ad blockers and iOS privacy settings.
Then check it. Place a test order, open Events Manager and make sure the purchase shows up once, with the right value. If it shows up twice, or with $0, every number in Ads Manager after that is wrong.
2. Get the catalog clean
The catalog is your product feed inside Meta. It powers dynamic ads that show people the exact products they looked at. Make sure titles are readable (not SKU codes), images are clean, prices match the site, and out-of-stock products drop out. A messy catalog means Meta is showing your ugliest, sold-out product to your warmest buyers.
3. Keep the campaign structure simple
For most Shopify stores I'd start with very few campaigns: one sales campaign optimizing for purchases (Meta's Advantage+ sales campaigns, which used to be called Advantage+ shopping, are built for exactly this), and a separate place to test new creative so a new ad doesn't have to fight your proven winners for budget on day one. Fewer campaigns means each one gets more purchases, which means Meta learns faster.
4. Feed it creative, constantly
This is where most of the work actually is. Ads wear out, and when they do, cost per purchase creeps up and everyone blames "the algorithm." The fix is new angles on a schedule: a founder talking to camera, a customer unboxing, a problem-and-fix demo, a plain product shot with a strong offer. Different hooks find different buyers.
I'd like to see 30 new ads added to an account every month, with the highest-confidence 10% of them getting real time and production budget. The other 25-27 are lower effort, but different in format and angle. That way you learn what makes your customer buy without sinking time and money into ads that never get much spend. Once you know what works, polish those few properly so they can become your evergreen winners.
How long before you know
Not after a weekend. You need enough purchases for the numbers to mean something, and Meta needs time out of its learning phase before its delivery settles down. Judge on cost per purchase and ROAS against your break-even number, not on clicks or CTR. Clicks are nice. Orders pay for inventory.
I let an ad spend for a week before I decide whether to kill it or scale it. Meta needs room to find your buyers and to even out normal platform swings (the algorithm can be a fickle and opaque beast), but a week is enough to gauge an ad's potential.
Mistakes I see on Shopify accounts
- Boosting Instagram posts and calling it a strategy. Boosted posts usually optimize for engagement, not purchases. You'll get likes from people who were never going to buy.
- Optimizing for add-to-cart because purchases are "too expensive." Meta will find you people who love adding things to carts. That's not the same people as buyers.
- Judging an ad on two days of data. See the coin-flip thing above.
- Sending traffic to the homepage. Send people to the product they just saw in the ad, with the price and the offer right there.
- No idea what break-even ROAS is. If you skipped that section, go back. I'll wait.
Should you run them yourself or hire someone?
If your budget is small, run them yourself for a few months. Set up the tracking right, test a few creative angles, and learn what your break-even number feels like in real life. If you're spending enough that a better cost per purchase is worth real money every month, that's when paying someone starts to make sense. I wrote up how Facebook ad agencies price their work if you want to run that math too.
If you want a second set of eyes on your store's ads, or just want to know what your break-even number should be, book a free call. Thirty minutes, I'll tell you what I'd do, and if the answer is "you're not ready to spend yet," you'll hear that too.