One of the more common and potentially confusing issues flagged in Google Search Console is the “Alternate page with proper canonical tag” notification. While it may sound innocuous, if not properly addressed, this issue can hinder your website’s ability to rank effectively in search results. Resolving canonicalization problems is essential for ensuring that Google indexes the correct version of your content and delivers improved visibility in organic search.
In this article, we will explore what alternate page canonical tag problems are, why they occur, how to diagnose them using Google Search Console, and most importantly—how to fix them thoroughly and correctly.
What Does the Notification Mean?
When you see the message “Alternate page with proper canonical tag” in Search Console under the Index Coverage report, it means that Google found multiple versions of the same content, but it has decided not to index this particular URL because it identifies a different page as the canonical version. In most cases, the canonical tag you set is respected, but this could also highlight an inefficiency, duplicate content handling issue, or misconfiguration that can impact your site’s SEO.
Understanding Canonical Tags
A canonical tag (rel=”canonical”) is used to tell search engines which page is the master version of a set of duplicate or near-duplicate pages. This tag helps consolidate link equity and avoid duplicated content in the search index.
For instance, if both:
show the same content, only one should be indexed, and the other should point to the canonical URL.
When the “alternate page” flag appears, it usually means Google thinks the current URL is a duplicate and has chosen another page as the one to index. That might be correct—or it might signal a deeper issue that needs investigation.
Why Alternate Page Canonical Issues Occur
There are several reasons why alternate page canonical tag issues may arise, including:
- Intentional duplication across different URL parameters
- Auto-generated duplicate pages by CMS platforms
- Multiple versions of the same site (with/without www, http/https)
- Poorly implemented canonical tags pointing to incorrect URLs
- Session IDs or filters adding non-canonical URLs to the index
- Self-referencing canonical tags missing or incorrect
The first step in fixing these problems is to correctly identify the affected URLs and understand how they’re behaving.
How to Diagnose the Issue in Google Search Console
Start by navigating to the Pages section under the Indexing report in Search Console. Locate the issue titled “Alternate page with proper canonical tag”, and click on it. This will show you sample URLs that Google considers duplicates and has chosen not to index.
Next, inspect an affected URL using the URL Inspection Tool. This will allow you to see:
- Whether the page is indexed
- What the user-declared canonical tag is
- What Google considers the canonical URL
If your canonical URL and Google’s selected canonical differ, it might be time to reevaluate how those tags are being implemented and whether they genuinely reflect what you want indexed.
Steps to Fix Alternate Page Canonical Issues
To properly resolve alternate page issues, take the following steps:
1. Ensure Correct Canonical Tag Implementation
Every page on your website should have a self-referencing canonical tag unless it is a deliberate variation of another page. Check that each page includes:
<link rel="canonical" href="https://www.example.com/your-page-url" />Use absolute URLs and ensure the tag resides inside the page’s <head> section. Avoid using relative URLs or pointing to incorrect versions such as staging sites or parameter-based pages unless necessary.
2. Remove or Consolidate Duplicate Content
If unnecessary variations of a page are being indexed, evaluate how you can eliminate them. This might include:
- Configuring your CMS to prevent auto-generated pages
- Blocking parameter-based URLs in robots.txt if they don’t serve real content variations
- Removing or 301 redirecting low-value duplicates to their canonical versions
Consolidation is a key step not only in resolving canonical issues but also in unifying ranking signals across duplicated URLs.
3. Verify Canonicals Are Indexable
Ensure that your canonical URLs:
- Return an HTTP status code 200
- Are not blocked by robots.txt
- Are not noindexed by a meta tag
Google will ignore canonical tags that lead to inaccessible or noindex pages, defeating their purpose entirely.
4. Eliminate Unnecessary URL Variants
Multiple versions of a URL can arise from:
- Trailing slashes vs. non-trailing slashes
- HTTPS vs. HTTP
- WWW vs. non-WWW prefixes
Standardize one version (typically HTTPS and with or without WWW) and use server-level 301 redirects to point all variants to the preferred version. Additionally, set your preferred domain in Google Search Console and in your sitemap URLs.
5. Submit Updated URLs for Indexing
Once corrections are made, re-inspect the affected URLs in the URL Inspection Tool and click “Request Indexing” to accelerate Google’s recrawling process. This helps fix issues more quickly and ensures your canonical corrections are reflected in the index.
Advanced Considerations
For large-scale websites, alternate page canonical issues may be systemic and require more advanced checks such as:
- Using a website crawler like Screaming Frog or Sitebulb to audit canonical consistency
- Cross-referencing data from server logs to detect how bots are accessing duplicate URLs
- Implementing hreflang with canonical tags in multilingual sites to prevent indexing conflicts
Common Mistakes to Avoid
When dealing with alternate page issues, be cautious not to:
- Use canonical tags to mask thin or doorway pages—Google may ignore misleading canonical tags
- Canonicalize paginated series to the first page—use rel=”next/prev” instead
- Assume Google will follow the canonical tag exactly—they use it as a hint, not a directive
Conclusion
Alternate page canonical tag notifications are not always errors—but they demand attention. By carefully auditing your website’s canonical setup and eliminating duplicate content, you can vastly improve indexing efficiency and ensure that your most important pages receive full ranking consideration.
In a digital ecosystem where crawl budget and content quality are more valuable than ever, addressing these issues is not just about SEO hygiene—it’s about strategic optimization. Prioritize fixing canonical discrepancies, and your search performance will reflect the effort.