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There are several ways to do this. The best way is to transfer all of your domain names to one domain registration site. In this example, I will say to use InstaPro.net since the price and terms of the deal are very good for the price.
The domain transfer process gets you a domain transfer, a one year domain renewal, plus any time you have left on the current expiration.
In order to transfer the domains, you are going to need to ensure that:
A) There is at least 10 days left before the domain to be transferred expires.
B) The current registrar has unlocked the domain to be transferred.
C) The current registrar gives you an authorization code to complete the transfer.
This process takes about 10 days to complete, so you will want to make sure to change your nameservers for hosting to GlowHost before you transfer the domains as they will become locked and uneditable for the duration of the transfer. If you do not have access to your DNS, your host or registration service provider should be able to do this for you upon your request.
Alternatively, if you can wait to change your nameservers until later (because no domains are about to expire) then you can begin the transfers of domains to get them in a safe place now, then edit your nameservers from InstaPro once they have been transferred to your account there.
InstaPro also offers Bulk Domain Transfers which will benefit you in the case of multiple domains.
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