As a web designer, I not only design websites, I also offer services such as web hosting and domain name registration. I have noticed lately, that increasing numbers of my customers hold many domain names for their businesses but only use one of them as a website. There are many myths surrounding domain names and especially around domain names and forwarding and its use for search engine optimisation. So I thought it would be useful to write about this and offer my advice from many years spent dealing with Internet sites.
The short answer to this is "no". The reason is that you could end up spending a fortune. You might start off with buying a .com and a .co.uk and then start worrying about .net, .org, .org.uk, .biz and the list goes on and on. You might then be tempted to buy different versions of your domain name, for example the same name but with dashes in the title. After this, you might think about keyword rich domain names related to your business. And before you know it, you find out you are paying out hundreds of pounds a year on domain names despite the fact that they are cheap to buy individually.
Unless you have a specific strategy that dictates otherwise then I would only buy the .co.uk version of your domain name (do not use dashes) and, if it is free, the .com version of your domain name. Choose one of them as your actual website address and forward the other one to it. Addresses such as .org, .org.uk, .net are for other types of organisations and are not really suitable for a business's main commercial domain name. Other addresses such as .com.uk are not real domain names at all and can be quite expensive.
There is no real benefit to your business to buy any more than this. The .co.uk and .com names carry the most authority for commercial sites and should be enough for any business.
Many people will buy domains that have they important keywords associated with their business but then do nothing other than forward them to their main commercial domain. In terms of search engine optimisation, this practice is of no value whatsoever. So do not waste your money if that is your intent. There are, however, two circumstances when it is worthwhile.
Firstly, as you are the owner of the domain name and retain the rights to it for as long as you renew, you are preventing someone else from buying the domain name and using it. This might be important to you if you think competitors could gain an advantage by owning it.
Secondly, you could create another website and fill it full of useful and relevant information, pointing people back to your website at every available opportunity. Make sure the content is useful and relevant or you could be penalised by the search engines. Making full use of a domain name in this way does make it very useful.
Save your money and only spend it on domain names that have a strategic importance and that you are going to use for a known and useful purpose. Otherwise, let others waste their money in this way.
Remember: owning a domain name and simply forwarding it to your website is of ZERO value in terms of search engine optimisation.