What Is a Subfolder?
A subfolder is the portion of a URL that appears after the main domain name and is separated by a forward slash. In the URL mybusiness.co.za/services/seo/, both "services" and "seo" are subfolders. They represent a hierarchical directory structure within the website, organising content into logical categories. Unlike a subdomain, a subfolder does not require a separate DNS entry and is treated by Google as part of the same root domain.
The SEO significance of subfolders is well established. Because a subfolder lives under the main domain, any backlinks pointing to pages within that subfolder contribute to the authority of the entire domain. When a respected South African news site links to a blog post at mybusiness.co.za/blog/article-name/, that link strengthens the whole domain, not just the blog section. This pooling of authority makes subfolder-based content a more efficient way to build SEO strength compared to isolated subdomains.
Subfolders also help users and search engines understand the structure of a website. A URL like smithlegal.co.za/services/commercial-property/ clearly communicates that commercial property is a type of service offered by the firm. Google reads this hierarchy when crawling and uses it to understand the relationship between pages. Well-structured subfolders support breadcrumb navigation, which can appear in Google search results and improve click-through rates by giving searchers additional context about the page they are about to visit.
Subfolder In Practice
A Pretoria digital marketing agency wants to rank across multiple South African cities. Using a subfolder structure, they create pages at agency.co.za/services/seo-johannesburg/, agency.co.za/services/seo-cape-town/, and agency.co.za/services/seo-pretoria/. Each city page sits within the /services/ subfolder, inherits the domain's authority, and benefits from internal linking across the site. This is far more effective than creating separate subdomains for each city, which would each start with zero inherited authority.
The same principle applies to e-commerce stores. A store selling clothing at fashion.co.za/womens/dresses/ keeps all category and product pages under the root domain. Every product page that earns a link or a social share adds to the collective domain authority, which lifts rankings across the entire catalogue. Choosing the right URL architecture, particularly the subfolder versus subdomain decision, is a core component of technical SEO and directly affects how quickly new content can rank in South African search results. It is also closely connected to how you structure your domain strategy overall.
Subfolders and site structure
A subfolder, also called a subdirectory, is a section of a website organised within the main domain using a path, such as example.co.za/blog or example.co.za/services/seo. Subfolders create a hierarchy that reflects how content is organised, grouping related pages under logical parents, which helps both users and search engines understand a site's structure and how its content relates. A sensible subfolder structure, shallow enough that important pages are reachable in a few clicks and logical enough that the path itself indicates where a page sits, makes a site navigable and its architecture clear. This is the standard way to organise content within one site, as opposed to a subdomain, which creates a somewhat separate section. Because subfolders keep content clearly part of the main domain, they are usually the default choice for organising a site's own content coherently under one roof.
Subfolders and SEO
Subfolders are generally favoured for SEO when the goal is to keep content unified under one domain's authority. Because a subfolder is unambiguously part of the main site, the authority and ranking signals the domain earns flow to its subfolders and vice versa, so content placed in a subfolder contributes to and benefits from the whole site's strength. This is why the common guidance is to put content you want to strengthen your main domain, such as a blog supporting your topics, in a subfolder rather than on a subdomain, which search engines may treat as somewhat separate. Subfolder depth should stay reasonable, since burying pages many levels deep makes them harder to reach and can weaken them, though the number of levels matters less than whether important pages are well-linked and easily found. The overarching SEO advantage of subfolders is consolidation: keeping a site's content and authority together under one domain.
FAQ
Should I use a subfolder or subdomain for my blog?
For most businesses, a subfolder is the stronger SEO choice for a blog. Content at mybusiness.co.za/blog/ benefits from the full authority of the root domain. Every backlink pointing to a blog post within a subfolder contributes to the overall domain strength. A blog on a subdomain must build its own authority from scratch and rarely achieves the same ranking results as equivalent content on a subfolder.
How deep should subfolder nesting go for SEO?
Best practice is to keep important pages within two to three levels of depth from the root domain. A URL like mybusiness.co.za/services/seo/on-page-seo/ is acceptable, but going deeper than three levels can dilute crawl budget and make the page feel less authoritative. Flat site architecture, where most pages are reachable within three clicks from the homepage, improves both SEO and user experience.
Should you use a subfolder or subdomain for a blog?
For most sites, a subfolder such as example.co.za/blog is preferable, because it keeps the blog clearly part of the main domain, so its content strengthens and benefits from the site's overall authority. A subdomain, which search engines may treat as somewhat separate, is better reserved for genuinely distinct sections.
How deep should subfolder nesting go?
Deep enough to organise content logically but shallow enough that important pages are reachable in a few clicks. The exact number of levels matters less than whether key pages are well-linked and easy to find; burying pages many levels deep with weak internal linking makes them harder to reach and can weaken them.