Microsites are often used by in-house teams and agencies to quickly launch new web content without having to modify the main corporate site.

Technically the name microsite implies an entirely separate website (i.e. different domain name), but in practice microsites can also be launched on a sub-domain, or in a sub-directory of the main domain. In any case, what separates the microsite from the main brand site is usually a different design, brand, content strategy, or information architecture – and often even the use of different technology than the main site (for instance, main corporate site is on SiteFinity, but the microsite is launched on WordPress).

Deciding which method to adopt is extremely important, with different options presenting different pros and cons. For the SEO-purist, the microsite (especially one on a separate domain) might be considered a poor strategy – diluting valuable link authority across multiple domains.

The reality, though, is that micro-sites are rarely created solely for SEO. Instead, brand and technology considerations typically drive the decision to build a separate site rather than add to the main brand site.

Let’s review the pros and cons of each option: separate domain, sub-domain, and sub-directory.

Separate Domain:

Advantages:

• Technological Independence: Break the shackles of your corporate IT overlords and go rouge! IT doesn’t have to touch this at all. An independent team or vendor can build, launch, and host the site themselves. This is often one of the core reasons microsites exist – for example, a marketing team wants to launch a simple blog, but is told by IT that their enterprise CMS doesn’t support blog functionality, or that to add blog functionality would be a 9-month project (usually with worse results and fewer features than an out-of-the-box WordPress installation).
• Brand Independence: This can take two forms. Sometimes a campaign will have a “stealth” stage – this is when the site is used to generate hype or interest around a particular topic or event, but it’s not immediately clear who is behind it. Only once publicity grows is the brand connection made in a hyped-up “reveal”. Alternatively, sometimes the parent brand will always be a part of the site – but kind of like the site’s sponsor (e.g. “brought to you by” or “inspired by”). This is common on many brand-publishing sites. While the site is a marketing vehicle for the brand, designing it like a semi-separate entity can give the site more perceived legitimacy as a publisher, rather than just a brand pushing it’s own products or services.

Disadvantages:

• Link Authority: You’ve just made SEO much harder for yourself. Large brand sites often have highly-authoritative domains, and placing your site on a separate domain prevents you from leveraging that authority. While you may get a few links from the brand domain, these are not nearly as powerful as having the site on the brand domain to begin with.
• Site Management: The independence from IT you so desperately craved can also be a burden. Once the initial excitement of the new site wears off, you still have a website to manage – which requires things like CMS updates, hosting, and domain name renewal. It may not sound so bad now, but as other marketing initiatives take priority, you’ll be begging for help from the IT team you scorned… and they’re probably not going to be happy about managing a new piece of technology that they had no part in acquiring.
• Cross-Domain Analytics: cross-domain tracking is kind of a b*tch. Analytics software using first-party cookies (like Google Analytics) can track across domains by passing the user ID through a URL parameter, but this doesn’t help if the user’s path between sites isn’t direct. Other software (like Adobe Analytics) can use third-party cookies, which do let you track across multiple domains, but third-party cookies are blocked and deleted more often. There are also more complex user identification methods you can use (like device fingerprinting), but these are not simple to set up and can raise privacy concerns with your users.

Sub-Domain:

Advantages:

• Immediate Brand Connection: When a company wants to have a strong brand connection from day one, a sub-domain can be a great way to go. For example: anvildaily.acme.com lets you establish a sub-brand for the site (The Anvil Daily!), but it’s still implicitly tied to the parent brand.
• Relative Technological Independence: Sub-domains are not bound to using the same technology as the main site. They can be easily pointed to another server, allowing you to use whatever technology you like to build and run the site.
• Easier Analytics: Sub-domains can be tracked using first-party cookies on the root domain. This gives a much clearer picture of how users interact with both sites. In Google Universal Analytics, cross-sub-domain users are tracked automatically – although you might want to set up a custom dimension or content group to easily separate out traffic on different domains – or add a filter to use full instead of relative URLs in your reports.

Disadvantages:

• Some Dependence on IT: You are going to have to make friends with IT a little bit here. They will manage the domain records, so if you were hoping to build this site without IT knowing about it (not that any of us would ever do that…), this isn’t the option for you.
• Long or Difficult to Remember Domain Name: Some companies are lucky enough to have short, simple domain names. But not everyone is that fortunate, and anvildaily.acmecorpnorthamerica.com doesn’t exactly roll off the tongue (or fit on a poster). Make sure you take this into account. In some cases, a separate marketing domain that redirects to the sub-domain could work for offline purposes (e.g. anvildaily.com redirects to anvildaily.acmecorpnorthamerica.com).
• Link Authority: While sharing a root-domain may be good for many things, SEO isn’t one of them. As far as we know, sub-domains don’t share authority with their root domain – so from an SEO perspective, you’re still starting with a brand new site.

Sub-Directory/Sub-Folder

Advantages:

• Inherit Domain Authority: www.acme.com/anvildaily/ inherits all of the domain authority from acme.com. This is a massive kick start to your SEO. I once had a client with a blog on a sub-domain that had had little success in generating organic traffic – we decided to relaunch the blog on-domain, and within weeks organic traffic increased 500%.
• Strong Brand Connection: A sub-directory makes it very obvious – both to those who visit the site and see the URL – that the site is associated with the core brand. This can also be reflected in the design of the site – some microsites use some of the global navigation elements from the parent site to make it easy to navigate between the microsite and the main site.

Disadvantages:

• Technical Difficulty: Now you’re really going to need make friends with your IT team. The sub-directory method usually means using the same server as the main site. This can be difficult if the main site is an older IIS installation (like many enterprise CMS’s use) and you want to use something like WordPress. While it is possible to install WordPress on some of these kinds of setups, it can be a very complicated process.

Making the Best Decision for Your Microsite

Campaigns involving microsites are launched for a variety of reasons and goals, and those objectives should drive the decision-making process for the domain strategy.

Short-lived campaigns, or those that aren’t planning on relying heavily on organic search, can certainly use a new domain or sub-domain. It’s a good idea to have an end-of-life plan in place for the site. Even if the campaign is wildly successful, do you want to keep maintaining the site in perpetuity? If not, you should have some plan to either roll the content up into the main site, or purposefully close down the site at the campaign’s completion.

Campaigns with a strong content marketing and organic search component should lean towards the sub-folder method, simply for the link-authority advantage. Unless the site has a long planned lifetime and budget for authority building and outreach, using a sub-directory or separate domain puts the site at an unnecessary disadvantage.

It’s true that the technological and IT hurdles for building a site in a sub-directory can be significant – IT departments are rarely excited about the idea of being responsible for another piece of technology. However, you should try exploring different options with them that could limit the amount of work they’ll ultimately be responsible for. For instance, a reverse-proxy can let you map a sub-directory to another domain. This allows you to use different technology to run the site, while still getting the site authority benefits of being on the same domain. Here’s information for Apache and IIS servers on setting this up.