Can you buy an iphone without a data plan?

My dad says I'll have to pay a monthly $20 data plan fee if I get a new iphone. The iphone I currently have is old and is my grandpa's old iphone. We do not pay a data plan on my iphone, but if I get a new one, will I? How can I avoid that?
Thank you so much! All information is appreciated!

All smartphones require a data plan. There are cheaper options on plans though. This is by far the cheapest plan available and it includes iphones. As always, make sure they have good coverage in your area or the main areas you travel between.
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Starting on January 11, 2013 in more than 2, 000 Walmart stores and online at Walmart.com, customers now have access to the iPhone 5 and iPhone 4 on Straight Talk's $45 no contract unlimited talk, text and data plan. To make this offer even more affordable, Walmart will be offering customers who purchase the phone in the store, a no interest fixed-monthly payments special financing offer for only $25 a month with a Walmart Credit Card.

No. You need data plan for it to work and you can't just buy a iphone without data.