Verizon and Sprint have both confirmed that they will carry the iPhone SE when it launches in the U.S. on Thursday, March 31. The carriers will also begin accepting pre-orders when they go live on March 24 at 12:01 a.m. PT. Neither carrier has announced specifics, but it's likely that the phone will be available both on-contract as well as with an installment plan.
If you want to purchase an iPhone SE without a Verizon or Sprint contract or leasing plan, you'll need to pay $399 for the 16GB model, and $499 for 64GB. Additionally, you can trade in an older iPhone for an iPhone SE and get the new four-inch phone for between $10 and $14 per month.
Update: U.S. Cellular has also confirmed plans to carry the iPhone SE starting March 31. Like the other carriers, U.S. Cellular will also begin accepting pre-orders on March 24.