Why this happens
Plug In SEO's scanner reads your page the same way Google does — it fetches the fully rendered page and counts every <title> tag it finds. If another SEO app (installed or previously installed) is also outputting a title tag, the scanner will flag both, even if you've never set that second one yourself and can't see it in your settings.
Step 1: See which pages are affected and what was found
Go to the SEO Scanner in Plug In SEO
In your Action Items, find the "Title Tag — Found Multiple" issue
Click the filter button next to the issue to see all pages flagged with this problem
Click on any page to open the Optimization Studio
Find the issue in the list and click the eye icon next to it
A panel will show you the exact duplicate title tags the scanner detected — use these to identify which one is yours and which one is coming from another source
Step 2: Double-check in your browser (optional)
The app already shows you the duplicate title tags in the eye icon panel, so this step is only needed if you want to verify directly in your page's code.
Open the affected page in your browser
Right-click anywhere → View Page Source
Press Cmd+F (Mac) or Ctrl+F (Windows) and search for
<title>If you see more than one result, the scanner is correct — two title tags are being output on your page
You can also open Chrome DevTools (right-click → Inspect → Elements tab) and search for <title> in the HTML panel.
Step 3: Find the cause
The duplicate is almost always caused by another SEO app. There are two scenarios:
The other SEO app is still installed — if you have another SEO app active at the same time as Plug In SEO, both may be outputting their own title tag. Check your installed apps in Shopify admin and confirm you're only using one SEO app for titles and descriptions.
The other SEO app was uninstalled but left code behind — even after uninstalling an app, its Liquid snippet may still be in your theme.liquid file, silently outputting a title tag on every page. To check:
In Shopify admin, go to Online Store → Themes
Click Actions → Edit code on your live theme
Open
theme.liquidPress Cmd+F / Ctrl+F and search for the name of the SEO app you previously used (e.g.
tinyseo,seo-manager,avada)If you find a
{% include 'appname' %}or{% render 'appname' %}line — that's the source
Step 4: Fix it
If the other app is still installed: uninstall it (or disable its title tag output if the app allows it). You can also reach out to that app's support team or use Shopify AI (available in your Shopify admin) for help removing it.
If the app was uninstalled but left a snippet behind:
In
theme.liquid, find the line with the{% include %}or{% render %}call for that appDelete it — or wrap it in comment tags to disable it safely:
Add
{% comment %}on the line before itAdd
{% endcomment %}on the line after it
Click Save
We always recommend backing up your theme before making code changes. In Shopify, go to Actions → Download theme archive to save a copy.
Step 5: Verify the fix
Go back to Optimization Studio for the affected page
Find the issue and click Recheck
The "Multiple Title Tags" warning should clear once the scanner only finds one tag
Legacy: still using Plug In SEO's old snippet code?
This section applies only if you installed Plug In SEO before December 11, 2025 and haven't migrated to Theme Extensions yet.
In that case, the duplicate may be caused by Plug In SEO's own snippet conflicting with your theme's built-in title tag. To fix it:
Open
theme.liquidSearch for
{% include 'pluginseo' %}Comment it out or remove it as described in Step 4 above
After fixing it, we recommend migrating to Theme Extensions so this doesn't happen again. You can check your migration status inside Plug In SEO.
Same issue with meta descriptions?
If your SEO check is flagging duplicate meta descriptions instead of title tags, the cause and fix are identical. See: Why does my SEO check say that I have multiple meta descriptions but I can only find one in the code?