Subdomain vs Subfolder vs Separate Domain (2025)
Subdomain vs subfolder vs domain is a structure choice that decides how your micro website shares authority, branding, and maintenance. Here’s the quick answer, comparison table, and a safe migration plan.
Verdict in one line: If the topic belongs to your main brand, choose a subfolder (e.g., example.com/micro/). Use a subdomain when you need technical isolation (app, docs, regional). Go separate domain only for distinct brands or PR/link strategies.
Quick Answer
- Subfolder — Best default. Shares authority, simplest crawling/indexing, lowest overhead.
- Subdomain — For different stacks/teams, docs, or regions with clean separation.
- Separate domain — For truly separate brands/partnerships and independent link building.
Best Option by Scenario
Expanding an existing category
Pick: Subfolder
- Create /micro-topic/ hub + supporting posts.
- Link from nav/footer; add contextual links from high-authority pages.
- Unify schema (Article/FAQ), breadcrumbs, sitemap under root.
Different stack or team
Pick: Subdomain
- Headless/docs/app flows without touching main stack.
- Strong cross-links both directions; same GSC property group.
- Share design tokens to avoid brand confusion.
Separate brand / partnerships
Pick: Separate domain
- Short domain, HSTS+SSL, CDN; clear brand stance.
- Independent PR/links; add
rel="sponsored"/nofollowwhere needed. - UTMs from parent; clear canonical plan.
Decision Flow (1-minute)
- Same audience & topic? → Subfolder.
- Needs different hosting/permissions/stack? → Subdomain.
- Distinct brand or PR push? → Separate domain.
- Unsure? Start with subfolder; you can split later with clean 301s.
Choosing subfolder first reduces time-to-rank and avoids duplicate infra work.
SEO Comparison Table
| Criteria | Subfolder example.com/micro/ |
Subdomain micro.example.com |
Separate Domain microexample.com |
|---|---|---|---|
| SEO equity from main site | High (shared authority) | Medium (more separate) | None initially |
| Crawl & indexing | Simplest (same robots/sitemap) | Separate mgmt | Separate mgmt |
| Brand separation | Low | Medium | High |
| Tech isolation | Low | High | High |
| Analytics segmentation | Filters/views | Clear (separate prop) | Clear (separate prop) |
| Link building lift | Leverage internal | Needs effort | Full effort |
| Maintenance | Low | Medium | Highest |
| Best for | Related micro topics | Docs, app, regional | New brand/partners |
Migration Checklist (Safe)
- Inventory & map: export all URLs, titles, top queries (GSC). Build 1:1 redirect map.
- Stand up target: publish identical content/meta at the new location.
- Canonicals & links: point canonicals to target; update nav, in-content links, breadcrumbs.
- Deploy 301s: server-level redirects for every old URL → new URL.
- Sitemaps: submit new sitemap; keep old sitemap + 301s live 2–4 weeks.
- Analytics: carry events/UTMs; annotate migration date.
- Inspect & fix: request indexing, resolve 404/soft-404/duplicates promptly.
- Re-link: add fresh internal links from authority pages to the new home.
- Track: watch rankings weekly; refresh pages that dip from pos. 6–20.
301 Examples
Apache (.htaccess) — subdomain ➜ subfolder
RewriteEngine On
RewriteCond %{HTTP_HOST} ^micro\.example\.com$ [NC]
RewriteRule ^(.*)$ https://example.com/micro/$1 [R=301,L]NGINX — subfolder ➜ separate domain
location /micro/ {
return 301 https://microexample.com$request_uri;
}Keep redirects for at least 12 months to preserve equity and backlinks.
Mistakes to Avoid
- Launching a subdomain without cross-linking from strong root pages.
- Using 302 or JS redirects instead of server-level 301s.
- Splitting thin content across multiple structures—consolidate one canonical.
- Forgetting to update sitemap, robots, and nav at the same time.
Set up your micro site the smart way
Choose the right structure now and avoid risky migrations later. Use our starter kit to launch with confidence.