Zero Benefit For SEO
If you purchase other domain names for your website, it won’t have any positive impact on your google ranking (SEO). The only time another domain name could be of benefit for your website, is when a domain name is used to point to a website and that, this site had a good ranking on Google. Then you could use this domain to redirect(using 301 redirect) it to your website’s main domain name. However if this site had a bad ranking or was penalised by Google, your website will inherit the “bad points”
But it can be helpful
If your official domain name syntax can be confusing for people, then having a simpler domain name can be a good thing. Let me give you an example.
Let’s say your company is a travel & tour agency specialised in Rotterdam, your company is called “Rotterdam Travel”, your main domain name could be something like www.rotterdamtravel.com, however not everybody knows that Rotterdam as 2 “t” and some people might type it wrong.
So, you could then have another domain like : “roterdamtravel.com” with one “t”, to make sure that you’re not losing any prospect because of a spelling mistake.
Google has also purchased the domain gogle.com (notice that the second letter “o” is missing)
Other Valid Reasons
You could have other domains:
- For each language of your site
- If your main extension is not a .com. For example: Doctors Without Borders have for main domain www.doctorswithoutborders.org, but they did also bought www.doctorswithoutborders.com