The 8 Most Common Hreflang Errors and How to Fix Each

Errors one through four

Missing return tags — page A points to page B but B doesn't point back — is the most common error and invalidates the whole cluster. Incorrect language/region codes, such as using 'uk' instead of the correct 'gb' for the United Kingdom (uk is not a valid ISO 3166-1 code; the correct code is gb), silently fail. Hreflang pointing to non-canonical or redirected URLs confuses Google about which URL is actually meant to rank. Hreflang pointing to a noindexed or blocked URL tells Google to swap to a page it isn't allowed to show, which Google will simply ignore.

Each of these is detectable by crawling your hreflang cluster and cross-checking status codes, canonical tags and robots directives against the declared hreflang targets — this is mechanical work best automated rather than done by eye.

• 1. Missing return tags (one-directional relationships)
• 2. Incorrect ISO codes (uk instead of gb is the classic case)
• 3. Hreflang pointing to redirected or non-canonical URLs
• 4. Hreflang pointing to noindexed/blocked pages

Errors five through eight

Conflicting hreflang and canonical tags — where the canonical points to a different URL than the one being referenced in the hreflang set — causes Google to consolidate the cluster onto the canonical target and effectively strip out the alternates. Missing self-referencing tags, where a page lists alternates but never lists itself, is treated as inconsistent by Google's documentation. Multiple URLs claiming the same hreflang value (two pages both declared as en-us) creates an ambiguous instruction Google can't safely act on. Relative URLs instead of absolute URLs in the href attribute are also a frequent, easy-to-miss bug that breaks the tag entirely.

Fix these systematically: build a validation pass that checks each of the eight patterns against every hreflang cluster on the site, and re-run it after every content or template deployment, not just once at launch.

• 5. Hreflang and canonical tags disagreeing on the target URL
• 6. Missing self-referencing hreflang tag
• 7. Two URLs claiming the same hreflang value
• 8. Relative URLs used instead of absolute URLs in href

Key takeaways

• ✓Memorise the eight patterns so audits are fast, not exploratory
• ✓Always check hreflang against canonical and robots directives together
• ✓Use absolute URLs and correct ISO codes without exception
• ✓Re-validate after every deployment, not just at initial launch

Why this lesson matters

This lesson belongs to Hreflang mastery, the part of International SEO where the goal is: write, validate and maintain hreflang so google serves the correct url to the correct market every time.

Read it once, then do it straight away on a real site inside RankTracker. Nothing here is theory for its own sake — every step produces something you can show a client.

Do it now

1. 1Open RankTracker with sample data already loaded, so you are not stuck on setup.
2. 2Track the keywords from this lesson.
3. 3Use RankTracker's hreflang crawl view to list every hreflang cluster on your site and flag any without matching return tags.