Do I have to pay extra money for “unlimited domains” in hosting plans which offer that option?
For example, FatCow and HostMonster both provide the "unlimited domains" feature as a standard of their hosting plans. They also provide a free domain upon startup. Does this mean that when a person is paying for a standard hosting plan including this feature, they don’t have to pay anything extra to add domains to their account and work with them?
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You can host unlimited domains. You still have to pay to register new domains. Usually about $15/yr for each domain.
http://www.webhostreview1.com
If you have unlimited domains, it usually means that you still have to pay to register all of your domains(mydomain.com). You can HOST as many as you want meaning, that a registered domain which you purchased is housed by your host.
Think of it as a car in a garage. Your host is the garage. They’ll let you put in as many cars (mydomain.com) as you want, but you still have to register them. You can do that either on your own, or through your host most likely. It is sometimes cheaper to find a place online to do it on your own, godaddy is pretty cheap for registrations. They’ll want your contact information and you have to renew it yearly. The free domain that you get with your hosting plan is really a free "registration".
When you registering for hosting which offer free domain name, you will get one domain name for free, taht offers: http://www.host1plus.com
But unlimited domains means that you could park as many domains as you need without any payment.
If you got one domain for free with your hosting plan (when you order new hosting), you no need to pay for it, but you will need pay next year. Because free domain offer often will be just for one year.
Hope answered.