In most cases your VoIP provider may have some experience with your current telecom service and may be able to tell you with a high probability if your number can be ported to their service. Rules have become more allowable for porting and will continue to become so as 2101 proceeds, but as rate centers and other information may be CLEC dependant, speak to your customer service rep at the porting in provider if there are any questions about your particular number. In some cases features that may be included with your number may have consequences on its portability, specifically if they happen to be business a business number and for instance that number is part of a hunt sequence on a business account. Additionally, the FCC has imposed new rules on interconnected VoIP providers recently that impose stricter policies and mandate more rights to consumers to keep their telephone numbers.