Verizon Wireless plans to close down the mobile broadband buffet for good, phasing out unlimited plans as customers upgrade from 3G phones to 4G. Verizon CFO Fran Shammo revealed the policy plan change on Wednesday while speaking at a J.P. Morgan conference, saying it must turn off the unlimited spigot as a prerequisite for moving to shared family data plans, FierceWireless reported.

Verizon ended unlimited data last summer, but it also grandfathered its old all-you-can-eat customers into their $30 plans in perpetuity. That practice now seems to be ending. Shammo said that Verizon will launch its data share service in mid-summer, which would eliminate the single device/single data plans it offers today. But Shammo added that those shared plans would be the only tiers it offers for 4G customers, meaning anyone upgrading from a 3G to 4G device would have to discard their unlimited plan and sign up for a monthly data tier, according to Fierce.

We’re not sure how this affects customers who carried their unlimited 3G plans over to 4G devices. Nor do we know if Verizon plans to shut down unlimited for all of its customers, even if they stick with 3G devices. It will be increasingly hard for them to do so, however, since Verizon plans to stop selling 3G-only devices and turn its entire smartphone portfolio 4G. We’re still trying to get more details from Verizon and will update when we know more.

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