Website expansion: subdomains vs subdirectories? Or a new domain?

Many websites grow at steady, continuous rates, and sometimes need to export content or be rearranged in order to adapt to their changing needs. Users wishing to expand the framework and distribution of their sites have many options at their disposal. For example, it’s possible to restructure websites via subdomains or directories. If a site’s content looks out of place after having been updated, then setting up a completely new site and/or a new domain may be in order. These approaches aren’t just structurally different, they also have a different effect on the website’s search engine optimization. Whereas subdomains were once the ideal SEO solution, today experts appear to be at odds with one another regarding which strategy works best.

Websites should always focus on a specific topic or theme. This can be narrowly defined (e.g. a blog about a particular celebrity) or feature a more free-ranging organization, like an e-commerce platform for electronics.

As the focal point of your web presence, content should always continue to be integrated into the site’s existing structure. Regarding the celebrity blog mentioned above, this would mean including news about the individual of interest. By the same token, the e-commerce platform should include information about new products on offer, such as smartphones or televisions. For those interested in starting up a completely new topic, however, restructuring the site or expanding it may also prove an appropriate move.  

If the new content is thematically similar to that of the existing website, a subdirectory or a subdomain may be enough to handle this change. Back to the example of a celebrity blog, these options may be suitable if content about the star’s spouse is now to regularly appear.

For content about other topics (e.g. posts about different celebrities that have nothing to do with current blog’s topic), a completely new orientation for the web presence may be necessary. For instance, instead of focusing on one particular actor or musician, it may be a good idea to cover the lives and careers of many different celebrities in general; what follows is a site that is more geared towards celebrity news rather than a portal about one single celebrity. In such cases, a completely new domain is often the best solution: with this option, the old site’s content will still be available; the only difference is that it’s now registered under a new internet address. A move like this can be especially useful for those aiming to build up a particular reputation or brand.

Which of these options is most suitable for you depends entirely on the orientation of your new content. The following points lay out the functions and distinctive features of each of these methods and demonstrate when they should ideally be used.

URL directories define website structures and are subdivided into different subdirectories that are connected to their domains. For an e-commerce platform, such a subdirectory may look something like this: www.example.com/shop. For producers with many different products, it may be useful to create subpages for the various items on offer; this can be done with the help of further subdirectories (www.example.com/shop/producer1, www.example.com/shop/producer2, etc.)

Good search engine optimization (SEO) requires a website’s subdirectories to always preside over appropriate names. As is the case for naming subdomains, subdirectory names should also be keywords. Not only is this important from an SEO perspective, doing this also helps boost transparency: landing pages for specific brands that don’t display their producers’ names, and instead are named according to no specific scheme, make sites look amateurish. This lack of professional tact offers users little reassurance of the site’s professionality and can have negative consequences for its reputation.

A website’s subpages can be organized into both subdomains as well as subdirectories. In comparison to the former, subdirectories have the advantage of being much easier to set up. Here’s a few general rules of thumb regarding their use:

• Content similar to that found on the main website but with its own specific topics is often placed in subdirectories

• When the planned content is substantially different than what’s featured on the current website, then many webmasters opt for subdomains

A subdomain refers to a domain that’s subdivided into further domains. As seen with the domain, www.example.com, the second-level domain, example, constitutes a subdomain for the top-level domain, .com. Following this pattern, the third-level domain, www., makes up a subdomain for the second-level domain, example.

Regarding a site’s website structure, however, subdomains refer to third-level domains. When, for example, a user wishes to set up an e-commerce platform under the domain, www.example.com, the subdomain, shop.example.com, can be chosen.

Some popular subdomains include:

• www. (World Wide Web)

• mail./smtp./pop3./imap. (Mailserver)

• ftp. (FTP servers)

• en./es./fr. (for language-specific websites)

• m. (optimized for mobile devices)

Manually setting up a subdomain is, for the most part, a complex task. There are plugins for implementing subdomains for many content management systems (including names like WordPress, Joomla!, and TYPO3, but these settings also have to be carried on the webserver; wildcards also need to be set up for this. These steps alone are enough to deter many non-experts. Some web hosting services, however, offer support or easier setups processes for subdomains.

Subdomains are especially useful when:

• Content is to be offered in different languages (en.example.com for English and es.example.com for Spanish)

• There are many different topics on a site, but a common theme still exists (flightprices.example.com vs. busprices.example.com)

• Different products are to be highlighted (producer1.example.com, producer2.example.com)

One question that many webmasters have to ask themselves: what’s better for SEO: a subdomain? Or a domain directory? As far as search engine rankings go, there are some differences to take into account: when it comes to subdirectories, both the quality of the root domain’s link power as well as the content itself can affect the ranking. Subdomains, on the other hand, aren’t at all connected to the root domain as far as SEO matters are concerned. When sites are evaluated by search engines, the root domain has a much smaller influence on the subdomains.

When changing domains, the same link juice (i.e. the previously achieved PageRank) and trust enjoyed by the original sites can essentially be transferred to new internet addresses. In order for this transfer to work, however, some SEO adjustments may be necessary. The most important ones are:

• Linking content with new domains

• Verifying the new address with Google Search Console (formerly Google Webmaster Tools) and entering your website’s change of address. This step needs to be carried out with the same account with which the old domain is registered.

• Set up a 301 extension from the old address to the new one (more information on this point can be found in our article on different types of domain redirects).

• Specify your website’s XML sitemap through Google Search Console. It’s recommended to immediately allow the sitemap to be crawled so that the Google bots are able to pick up on this as soon as possible.

• Keep an eye on your site’s stats over the coming weeks (ideally by using additional analysis tools). For larger sites, Google even recommends monitoring these figures for a half year.

Those who decide to create a new website with a previously unused domain should start from scratch. Here, you’re starting from zero as far as SEO is concerned; in some cases, this fresh start can also be an advantage.

Advantages:

• Subdirectories strongly benefit from the main website’s content and link juice more than subdomains do. This is because subdirectories receive these two important aspects directly from the main site and in the same form.

Disadvantages:

• When directories are hit with an algorithmic penalty from Google, complete root domains are affected along with their rankings.

Advantages:

• Generally, a maximum of two search results refer to a single domain. By using a subdomain, it’s possible to have additional hits appearing in the search results.

• When Google penalizes subdomains, neither root domains nor any subdomains are affected. Conversely, the same applies when the main site or other subdomains are punished.

Disadvantages:

• Each subdomain has to be individually optimized for keywords and link building strategies

• Subdomains don’t stand to gain as much from their corresponding site’s content (the opposite relationship is also true) as subdirectories do. The same applies for backlinks. This is because connections from subdomains to the root domain are given the same rating as an external domain, namely a score of ‘1’.

Advantage:

• Link juice and trust can be transferred from old domains to new domains

Disadvantage:

• For larger websites, time-intensive work is needed for subsequent monitoring efforts of the site.

New websites and SEO

Advantages:

• Existing online web presences that have been penalized by search engines (or simply have a poor SEO ranking due to other factors), can be countered by building up and optimizing a completely new website.

• Additional websites can be optimized with backlinks for specific countries or language regions.

Disadvantages:

• New websites don’t gain any of the previously achieved SEO results from any preceding sites.

• The cost of creating content and (link) marketing increase with new websites.

Whether new content should be incorporated into subdirectories, subdomains, or an entirely new domain/website depends on the site’s overarching theme. This theme should be of top priority and those responsible for content should ensure that new material doesn’t fall too far out of line with these common topics.

If it’s in alignment with your site’s content scheme, you can incorporate material from an existing page via subdirectories or subdomains. If this step proves to be relevant, it’s important to keep in mind that setting up a subdirectory is, for the most part, easier than getting a subdomain up and running. Regarding the website’s structure, subdirectories tend to be the preferred option as long as the planned content resembles that of the original site. The greater the difference is between the existing site and the new content, the better it is to go for the subdomain option.

Additionally, a site’s SEO strength can also determine whether subdomains or new directories should be used. Given that subdomain penalties don’t affect root domains or other linked subdomains, this solution should especially be used in portions of the site that cannot be 100% controlled by webmasters (e.g. forums whose user-generated content often features substandard or questionable content).