Meta Shows Fewer (or More) Purchases Than Shopify After August 26, 2026: How to Fix It

If Meta Ads Manager started reporting fewer purchases than your Shopify orders in late August 2026, you are not alone. One of the most-read threads on the Shopify Community this autumn is a merchant asking why Meta shows fewer purchases after the August 26 checkout upgrade. Another, with almost fifty replies, is about the opposite problem: a Purchase event that fires on the homepage when nobody bought anything.

Both problems usually have the same root: purchase tracking that was built for the old Thank you page. This guide explains what changed, how to tell which problem you have, and how to set up purchase tracking that matches your orders.

What changed on August 26, 2026

On August 26, 2026, Shopify upgraded the Thank you and Order status pages for stores that were not on Shopify Plus. Plus stores had already been through the same change. After the upgrade:

• Additional scripts stopped running. Code pasted into the Order status page "Additional scripts" box no longer runs.
• Script tags stopped on the Order status page. Apps that injected tracking through script tags lost that page as well.

Many stores fired their Meta, Google Ads, and TikTok purchase events from exactly these two places. When they stopped, the purchase events stopped with them. Nothing showed an error. The first sign was usually a drop in reported purchases and ROAS while Shopify orders stayed normal.

Find out which problem you have

Compare Meta purchases with Shopify orders for the same days, ideally two weeks before and after August 26.

• Meta is much lower than Shopify: purchase events are missing. Usually the old purchase code stopped running and nothing replaced it, or the replacement only runs for some customers.
• Meta is higher than Shopify, sometimes close to double: purchase events are counted twice, or fire when no purchase happened. Usually two setups now send the same purchase, or a script fires Purchase on the wrong page.
• Meta is a little lower than Shopify: this can be normal. Ad blockers, browser restrictions, declined consent, and orders created outside the online store all lead to some difference. Agree on an acceptable gap instead of chasing a perfect match.

Then open Meta Events Manager, select your dataset, and check where Purchase events come from. You can see whether they arrive from the browser, the server, or both, and whether events are being deduplicated.

The setup that matches orders

For most Shopify stores the cleanest setup is one source of purchase events with a server-side copy.

1. Use Shopify's Meta integration as the single source

Shopify's Facebook & Instagram app sends events through the Meta pixel and, depending on your settings, through Meta's Conversions API from Shopify's servers. Shopify describes three data sharing levels: Standard, Enhanced, and Maximum. At Maximum, your store uses both the Conversions API and the Meta pixel. Choose the highest level that your privacy policy and consent setup allow.

The server-side copy matters most after the upgrade. A purchase sent from Shopify's server does not depend on a script running in the customer's browser on the Thank you page.

2. Remove the old purchase code

Look for every other place that still sends Purchase:

• the Order status page "Additional scripts" box, which no longer runs and should be emptied to avoid confusion later;
• fbq('track', 'Purchase'...) calls in theme.liquid, sections, or snippets;
• Google Tag Manager containers with a Meta purchase tag;
• other pixel apps or server-side tracking tools connected to the same dataset.

A Purchase event in theme code is a common reason for purchases on the homepage or product page. Theme code runs on storefront pages, not on checkout pages, so a purchase event there either never sees a real order or fires on the wrong page.

3. Use a custom pixel only when you need one

If you need a setup the Meta app cannot provide, add a custom pixel under Settings, Customer events. Custom pixels run in a sandbox and subscribe to Shopify's customer events. A purchase belongs on the checkout_completed event:

// Paste Meta's base pixel code above this line, as Meta provides it.
analytics.subscribe("checkout_completed", (event) => {
  const checkout = event.data.checkout;
  fbq("track", "Purchase", {
    value: checkout.totalPrice?.amount,
    currency: checkout.currencyCode,
  }, { eventID: event.id });
});

Do not run this next to the Meta app for the same dataset unless you know how the two are deduplicated. Two browser purchase events for one order inflate your numbers.

4. Make deduplication work

Meta merges a browser event and a server event into one purchase only when both have the same event name and the same event ID. If the browser sends Purchase without an ID and the server sends Purchase with one, Meta counts two purchases.

Meta also cannot merge the same purchase when two different server-side tools send it. If you use a third-party Conversions API tool, either let it own purchases and turn off the overlapping Shopify data sharing, or the reverse. Running both on one dataset is a frequent cause of double counting.

Test with a real order

1. Open Events Manager, choose your dataset, and open Test events.
2. Place a real order on the storefront with a low-value product or a 100% discount code.
3. Confirm that exactly one Purchase arrives, with the right value and currency, and that browser and server events show as deduplicated.
4. Browse the homepage and a product page without buying and confirm that no Purchase event appears.
5. Repeat with consent declined if you use a consent banner, so you know what happens for those visitors.

Repeat the comparison of Meta purchases and Shopify orders after a few days of normal traffic.

Do the same for Google Ads, TikTok, and GA4

The August 26 upgrade affected every platform that relied on Additional scripts, not only Meta. Check Google Ads conversions, TikTok events, Pinterest, and GA4 the same way: one source per purchase, server-side where the platform supports it, and a test order to confirm. Our GA4 ecommerce tracking guide covers how to validate GA4 purchases against Shopify orders.

If your session and conversion rate numbers also changed in late September, that is a separate change in how Shopify counts sessions. Read why your Shopify sessions changed after September 21, 2026 before you connect the two.

Checklist

• Compare Meta purchases with Shopify orders before and after August 26, 2026.
• Decide whether purchases are missing, doubled, or within a normal gap.
• Use the Meta app at the highest data sharing level your consent setup allows.
• Remove Purchase events from Additional scripts, theme code, and Tag Manager.
• Keep one server-side source per dataset.
• Confirm deduplication and test with a real order.
• Check Google Ads, TikTok, and GA4 the same way.

Black Friday is the worst time to discover broken purchase tracking, because ad spend decisions are made from these numbers. If your purchases still do not match, tell us what you see. Shopimaster can audit every tag on your store, rebuild purchase tracking on Shopify's customer events, and verify it with test orders before November 27.