Multiple Domain Names – Content Duplication Penalties

Multiple domain names registered? If you own a website AND you have more than 1 domain pointing to your content, you might want to read this with your full attention. There are a great many websites out there which, by inappropriate use of multiple domain names, effectively cripple their search engine rankings by blatantly breaching search engine guidelines! Site owners often register more than one domain, and there are sound reasons for doing this, including;

  • The main URL includes a keyword phrase but is too long to type quickly, so a shorter, cryptic one is utilised and maybe is also used on business cards and letterheads.
  • You take various versions of domains to prevent competitors from grabbing them – .com,,.biz, .info etc, and point them all to the “main” site.
  • You take various country versions –,, because you are going to expand into those markets – but in the interim, you point them all to the “main” site.

There are also misguided reasons for doing this, including;

  • Having multiple domains pointing to the same location in the hope that the search engines will be duped into indexing ALL of them as different content, gives you lots of top rankings under different domains.

A well-planned SEO audit checklist will ask this question “How many domains do you have, and where are they pointed?”…

Search engines hate duplicate content with a passion… but their automated spiders and bots cannot determine which category YOU fall into – uninformed and innocent of intent, or deliberately and knowingly manipulative. So all sites who transgress can expect to be treated equally. And yes, you can be banned from the SE indexes for getting it wrong!

The search engines do not give out many guidelines – in fact, they are all very coy about giving too information much away. However, when they do make a statement by way of guidelines, regardless of how politely it is worded, you had best sit up and take notice because they are really, really serious about it!

    Google Guidelines on Multiple Domains

    In the case of Google, their Webmaster Guidelines are unambiguous! E.g. on this page;

    Quality Guidelines – Specific Guidelines

    • Don’t employ cloaking or sneaky redirects.
    • Don’t create multiple pages, subdomains, or domains with substantially duplicate content

    What This Means to You

    There is a clear and present danger in having multiple sites pointing to the same location if they load exactly the SAME content – this is a SERIOUS breach of Google’s Webmaster Guidelines and is expressly FORBIDDEN because the search engines can only interpret this as a blatant attempt to generate duplicate content under different URLs. Regardless of your actual intentions in this, it’s likely to result in a BAN from search engine indexes. 🙂 Not a good start to an online presence, right?

    Ignorance of The Law is No Excuse

    Ignorance of search engine guidelines is not a valid excuse either! Unfortunately, many web designers and hosting companies are blissfully unaware of the correct way to implement multiple domain names. The result is that many website owners unknowingly jeopardise their site’s inclusion in the search engine rankings.

    My advice is that if you have more than one domain name, you check how it’s been set up.  If you have two domains; and and BOTH load the same pages but with the different domains showing, then you have a problem. If you can also load the sites as and then totals 4 different ways of indexing the SAME content!

    The Right Way to Do It

    That said, it IS permitted to have multiple domains pointing to the same content BUT it may only be done via the use of a Permanent 301 Redirect being applied to the secondary domains, e.g. typing in the URL for any of the secondary domains will redirect you to the main site. This change can easily be implemented, at no cost other than a few minutes of time. I can sort this out for you as part of any of the SEO packages offered.

    In this example, is redirected to and neither visitors nor SE spiders ever “see” content under the secondary domain name. The same logic should also be applied to the non-www versions of both domain names to complete the process and prevent potential conflicts with the search engines.

    Multiple Domain Name References

    Page last updated on Wednesday, October 11, 2023 by the author Ben Kemp