Your father owes no tax. There is no penalty. Unless he exceeds a lifetime gift limit of over 12 million dollars, there is no tax owed for the gift he gave you. Have your father check his online account with the IRS to see if it shows the Form 709 was received. Or he can call the IRS.
https://www.irs.gov/payments/your-online-account
To call the IRS:IRS: 800-829-1040 hours 7 AM - 7 PM local time Mon-Fri
Listen to each menu before making the selection.
First choose your language. Press 1 for English.
Then do NOT choose the first choice re: "Refund", or it will send you to an automated phone line.
Instead, press 2 for "personal income tax".
Then press 1 for "form, tax history, or payment".
Then press 3 "for all other questions."
Then press 2 "for all other questions." It should then transfer you to an agent.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
