Why wasn't my tax refund deposited in my bank account?

Well ... did the IRS/State release the refund yet ?   Did you check the routing & account number with your bank for accuracy ? 

Does this IRS "Where's My Refund" tool say your funds have actually been sent?
http://www.irs.gov/Refunds

Were you having the refund direct deposited to your bank account directly ?

If the IRS has actually sent the funds, the IRS FAQ page says to allow "up to 5 days" due to variations in bank processing procedures and times.

If so did you enter the correct routing & account number for an ACH transfer ?  Here is how you can see your deposit information:

Your direct deposit information will be at the bottom of your Form 1040.

To view your 1040 after filing, Sign into TurboTax > Taxes > Tax Timeline > Some other things you can do > Download/print (.pdf). 

Please see the following FAQ article below if you entered in the wrong bank account information.

https://ttlc.intuit.com/questions/1901677

Did you have the TT fees withheld from the federal refund and are getting the refund on the Turbo Tax Debit card?

If so the refund needs to go from the IRS to the third party bank to the card.  This process can take up to 3 business days or more.

Check the IRS :  https://www.irs.gov/Refunds

Check  SBTPG:  by logging into their website at:  https://cisc.sbtpg.com/

Or you can get 24-hour automated info by phone at:  https://cisc.sbtpg.com/contact.aspx

Check at Turbo Tax Visa :  If you have any questions or need assistance with your Turbo Prepaid Visa Card, please visit TurboPrepaidCard.com or call us toll-free at (888) 285-4169.

Did you have the TT fees withheld from the federal refund  and then the balance sent to your bank account or debit card ?

If so the refund needs to go from the IRS to the third party bank to your bank account.  This process can take up to 3 business days or more.

Check the IRS :  https://www.irs.gov/Refunds

Check  SBTPG:  by logging into their website at:  https://cisc.sbtpg.com/

Or you can get 24-hour automated info by phone at:  https://cisc.sbtpg.com/contact.aspx