Yes, you do. I'm guessing you are thinking about buying a used phone off ebay or something of hte sort; i would recommend against it. You will automatically be signed up for the $30 data plan. The Kin Onem is already only $20 w/ a new contract, and other phones are rather cheap too, so if you are eligible for upgrade i would personally suggest buying new. If you are still on-contract and can't get the upgrade prices, which is what i'm guessing is your situation, be careful as to what phone you do end up buying. For one, you have situations like this where the phone is a completely different model, and online, you may have vague information, or even faulty information before your purchase. Secondly, if the phone was reported stolen or lost, its serial number will directly be reported to Verizon (by the old owner; this is necessary for htem to get their replacement), so if you do end up unknowingly buying a stolen/lost phone, it won't work, at least without doing 'under-the-table' stuff to it. I would recommend not upgrading if you don't have to, mid-contract. If you are replacing a broken phone, that is understandable, but is waiting 2 years for a new phone really that long? If anything, just sign a 1-year contract if you find yourself wanting to upgrade more periodically. The discounts are slightly less, but it overall will make up for buying phones for high prices mid-contract if that happens to be your situation.
I'm not advocating against used phones (even though it sounds like it); many used phones are great and their former users are just selling them because they have a new one. However, the integrity of used item sales, especially technology, is rather lacking, sadly. I'm just telling you my opinion on these things, but good luck on finding what you are searching for.