Why Meta and Shopify never match

By Moisés · Updated October 2026

Say Meta reports 120 purchases this week, and Shopify shows 85 orders from ads. Nobody is lying. The two count different things, on different days, with different rules. Here is why the numbers drift apart, when a gap means something is broken, and which number to trust for each decision.

Why don't the numbers match?

Shopify counts the orders that came in. Meta counts the orders it believes its ads helped cause. Six differences explain most of the gap:

• Meta counts views, not only clicks: by default, Meta credits a purchase to an ad if the person clicked it in the last 7 days or saw it in the last day. Someone who saw your ad on Monday and bought on Tuesday from a Google search counts as a Meta sale.
• Shopify credits the last click: its reports give the order to the last channel that brought a visit, like a search or an email. It never sees the ad someone watched without clicking.
• Every platform claims the sale: if a buyer clicked a Meta ad, then a Google ad, then bought, both Meta and Google can count that one order. Add the platforms together and you often get more sales than your store had.
• They file sales on different days: Ads Manager puts a purchase on the day of the ad view or click, and Shopify on the day of the order. Different time zones move late-night orders to another day too.
• Some of Meta's sales are estimates: since Apple's privacy changes in 2021, Meta can't see every purchase made on an iPhone, so it models part of them.
• Refunds never reach Meta: Meta keeps the value your pixel sent at checkout. Shopify subtracts returns and refunds later, and handles taxes and shipping by its own rules.

Which number should you trust?

Each one is right for a different job.

• Shopify, for what came in: it counts real orders and real money. Use it for revenue, profit, and whether the business grew.
• Meta and Google, for comparing ads: inside one platform, every campaign is measured with the same rules. Use those numbers to decide which ad or campaign gets more budget, not to add up your revenue.
• Your blended number, for the budget: total sales in Shopify divided by total ad spend across every platform. It ignores who gets the credit and asks one question: when spend went up, did sales follow?

That blended number is often called MER, for marketing efficiency ratio. At $10,000 in total ad spend and $40,000 in sales, your MER is 4. Track it each week next to the platform numbers. If Meta's return keeps climbing while your MER stays flat, Meta is taking credit for sales you would have made anyway.

When should a gap worry you?

A steady gap is normal. A gap that moves for no reason usually means broken tracking. Look closer if:

• Meta reports more purchases than your store had orders in total, from every channel.
• The gap jumps from one week to the next, and nothing changed in your campaigns.
• Meta shows a purchase value far above the order values in Shopify.
• Meta reports almost no purchases while Shopify keeps selling to visitors from your ads.

The usual causes are a purchase event that fires twice, a theme or app change that removed the pixel, or a value sent in the wrong currency. Fix the tracking before you change any budget, or you'll be moving money on bad numbers.

How do you bring the numbers closer?

• Send purchases from your server too (on Meta, the Conversions API), with an event ID so each order counts once.
• Check that your ad account and your store use the same time zone and currency. If they don't, compare by week, not by day.
• Compare the same dates and the same attribution setting every time, and write down which one you use.
• Tag every ad link with UTM parameters, so Shopify can see which visits came from your ads.
• Judge weeks and months, not single days. Sales keep arriving for days after an ad runs.

How do you know the ads really work?

Attribution tells you who gets the credit. It doesn't tell you what would have happened without the ads. To answer that, test it: cut the ads in one region or for a few weeks, and watch what your total sales do. If sales barely move, the platform was claiming sales you would have made anyway. If they drop, the ads were doing the work.