If you plan to message US numbers after porting your number to a provider like OpenPhone, we recommend signing up for an account and completing carrier registration before you start the porting process. Registrations may remain pending for up to 30 days, but we’re currently receiving some approvals in as quick as 5-7 days. In cases where your information is unable to be verified expediently, it may take longer than 30 days. Due to emerging regulations pushed for by the large US cell providers, you aren’t able to message US numbers until registration is approved. Once your registration is approved, start the porting process two weeks before you’re ready to switch providers. That’s how long it takes to port your number over to your new provider. You can continue using your number with your existing provider until the porting process is complete as long as you keep your account active with them. Then, after your number is ported over, you can cancel.