Homepages that lose AggregateRating markup after a platform switch
| Group | Lost AggregateRating | Sites with it before |
|---|---|---|
| Moved to Shopify | 68.3% | 60 |
| Left Magento | 60.0% | 35 |
| Left WordPress | 57.8% | 45 |
| Moved to Next.js | 49.0% | 100 |
| All switchers | 57.1% | 217 |
Source: PageSpeed Matters, Sept 2026. Groups overlap: a site can appear under both its old and new platform.
Summary
AggregateRating markup tells search engines a page's average review score and review count. It is one of the structured data types that can make a site eligible for review stars in search results, and it is easy to lose in a rebuild because it often comes from a reviews app, plugin or template that does not carry over.
We checked how often it survives a platform switch. Of 217 top 1M homepages with AggregateRating markup the month before a switch, 57.1% had none the month after.
What we measured
We used HTTP Archive monthly crawls of the top 1M sites from September 2024 to September 2026. A site counts as switching platform when it ran on one platform for 3 or more months and then on another for 3 or more months. We compared the structured data types on each homepage in the month before the switch with the month after.
This is a short study. The base is 217 homepages, and only four breakdown groups reach 30 sites (35 to 100 each), so the group results are indicative. We checked homepages only, not product or review pages. The base covers every switcher with the markup, not only ecommerce platforms, so we call them sites rather than stores.
More than half of sites drop review markup
57.1% of the 217 homepages that had AggregateRating structured data before a switch had none after it. Moves to Shopify dropped it most often, at 68.3% of 60 homepages, against 49.0% of 100 homepages moving to Next.js. By previous platform, 60.0% of 35 sites leaving Magento and 57.8% of 45 leaving WordPress lost it.
New markup rarely makes up the loss. Only 2.7% of 1,472 sites that arrived on Shopify without AggregateRating had it after the move, and 2.2% of 1,404 Next.js arrivals. So the sites that lose review markup are not balanced out by sites that gain it.
Product markup goes the same way. 81.3% of 171 homepages with Product structured data before the switch had none after. Review and product markup often come from the same templates and apps, so when those are rebuilt, both likely go together.
57.1%
Share of 217 top 1M homepages with AggregateRating markup before a platform switch that had none the month after.
What this means for your site
Before a migration, list every structured data type your key templates output, including AggregateRating, Review and Product, and note which app or plugin produces each one. Make the new platform's reviews app and templates part of the launch checklist, not a later task.
After launch, test your homepage and your main product and review pages with Google's Rich Results Test, and watch the rich result reports in Search Console for the following weeks. If review markup is missing, it is often one app setting or one template change to restore.
Sources
- HTTP Archive monthly crawls, top 1M sites, September 2024 to September 2026
- Google Search Central, review snippet structured data: https://developers.google.com/search/docs/appearance/structured-data/review-snippet
- Schema.org, AggregateRating: https://schema.org/AggregateRating
Embed this research
Paste this on your site to embed the chart. It links back to the source automatically.
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<p style="font:14px/1.5 system-ui,sans-serif">Source: <a href="https://www.pagespeedmatters.com/resources/data-studies/review-schema-lost-in-migration">Review Schema Lost in Migration: 57.1% of Sites Drop It - PageSpeed Matters</a></p>
Frequently asked questions
Do sites lose review schema when they migrate platforms?
Often. Of 217 top 1M homepages with AggregateRating markup the month before a platform switch, 57.1% had none the month after.
Which platform moves lose review markup most often?
In our small sample, moves to Shopify lost it most often, at 68.3% of 60 homepages, against 49.0% of 100 moving to Next.js. 60.0% of 35 sites leaving Magento and 57.8% of 45 leaving WordPress lost it.
How do I check if my review markup survived a migration?
Run your homepage and key product pages through Google's Rich Results Test and check Search Console's rich result reports. In our data, only 2.7% of Shopify arrivals without AggregateRating gained it after the move, so review markup rarely appears on a new platform on its own.
Review markup is usually one app or template setting away from coming back, and it is far easier to keep through a launch than to rebuild after. Need help with this? See our ecommerce migration services.