One of the summary screens in TurboTax shows a combined refund total for both state and federal. Make sure you are comparing your refund amount with just the state or federal alone.
If you have your TurboTax fees paid from your federal refund, those fees plus a $40 processing fee will be taken out of your refund before it is sent to you.
If neither of these explanations is the reason for the reduction, the IRS or state has adjusted your refund for some reason. This IRS topic gives some of the reasons for an offset: https://www.irs.gov/taxtopics/tc203
If the IRS was the reason, you should receive a letter explaining what they did.
