Here are a couple of possibilities:
Be sure you are only considering the Federal refund and not a "total refund." A state refund, if applicable, comes separately.
Or is it this:
Did you choose to pay any TurboTax fees out of the Federal refund? If so, in addition to the product fees that option also has an additional 39.99 service fee (44.99 for California filers.)
If you used Self-Employed Edition, here are typical fees:
Federal return 119.99
State return 44.99
Option to pay fees out of the Fed refund: 39.99 (or 44.99 for California filers)
Plus possible sales taxes