If you've ever worked with older WordPress setups or followed early SEO advice, you've probably seen guides recommending that you rewrite URLs to replace underscores with dashes. That advice used to matter a lot, but the search landscape has shifted. Today, Google handles underscores differently, WordPress handles slugs better, and modern redirect tools have replaced most old .htaccess tricks. This guide breaks down whether you still need underscore to dash redirects, what Google actually recommends today, and the best ways to handle URL cleanup on a modern site.
Do You Still Need to Redirect Underscores to Dashes in URLs?
SEO used to be full of rules about the correct way to format URLs, and one of the strongest recommendations was to always use hyphens. Years ago, Google treated underscores as word joiners, which meant that a URL like example.com/my_tag would look like a single word instead of two. Today, that is no longer the case.
How Google Sees Underscores vs Dashes Today
Google has treated underscores as valid word separators for years now. Hyphens are still the preferred choice for readability and consistency across the web, but underscores do not harm SEO performance. If your only concern is whether underscores affect rankings or keyword recognition, the answer is no.
Should You Rewrite Tag URLs in WordPress?
WordPress automatically uses hyphens in new slugs, so underscores usually appear only in older sites or imported content. Before rewriting anything, consider how important your tag URLs really are. Most modern SEO strategies recommend noindexing tag archives because they often produce thin content and duplicate listings.
If your tag URLs are indexed and performing well, you should avoid mass rewrites. If they are outdated, inconsistent, or causing crawl issues, then cleanup can help, but it should be done carefully.
Modern Options for Fixing Underscore URLs
You have three solid approaches depending on your goals.
1. Update Tag Slugs Inside WordPress
For most sites, the easiest and safest solution is to edit the slugs in WordPress:
- Go to Posts > Tags
- Edit a tag.
- Change the slug to use hyphens instead of underscores.
WordPress will handle the change and, depending on your setup, may automatically apply redirects or work smoothly with a redirect plugin.
2. Use a Redirect Plugin
Redirect plugins like Rank Math, Yoast, SEOPress, or Simple 301 Redirects give you more control and safer management than .htaccess edits. Benefits include:
- Easy bulk redirects
- Automatic handling of www, HTTPS, and trailing slash variations
- No risk of breaking your entire site
- This is the recommended method for most users.
3. Use .htaccess Only If You Must
If you are comfortable editing .htaccess and need a server level solution, you can still redirect underscores to dashes. The old examples floating around the web often hardcode domains or use deprecated directives. Here is a modern, safer version:
RewriteEngine On RewriteCond %{REQUEST_URI} ^/tag/ [NC] RewriteRule ^tag/(.*)_(.*)$ /tag/$1-$2 [R=301,L]
This approach:
- Avoids hardcoded domains
- Respects your site's canonical settings
- Only triggers inside /tag/ so you do not break plugin directories, uploads, or system files
Do Underscore Redirects Still Matter for SEO?
Not really. The original problem that made these redirects necessary has been solved by search engines for years. The real SEO focus today is on:
- URL clarity
- Crawl efficiency
- Avoiding duplicate content
- Maintaining stable URLs
- Consolidating thin or low value tag pages
Changing URLs purely for hyphen consistency rarely produces meaningful SEO gains.
When You Should Still Clean Up Underscore URLs
There are a few cases where cleanup makes sense:
- Your site migrated old content with mixed slugs
- You want consistent branding across all URLs
- You are optimizing a very large site with strict URL formatting rules
- You are removing tag duplicates or reorganizing your taxonomy
In these cases, hyphens make your URLs cleaner and easier for users to read. Just be sure to redirect everything properly.
Bottom Line
Redirecting underscores to dashes used to be essential SEO maintenance. Today, it is optional and only helpful in specific cases. Modern WordPress sites should rely on updated slugs, redirect plugins, and smart indexing strategies rather than global .htaccess rewrites.