The filing thresholds for needing to file Form 8938 are different from the filing thresholds for an FBAR. For married couples filing jointly, the filing threshold is $50,000 on the last day of the tax year or $75,000 at any time during the tax year. For more information on Form 8938 see, Do I need to file Form 8938, Statement of Specified Foreign Financial Assets?
I would recommend to start filing as soon as you realize you need to file. The FBAR has the same due date as the federal income tax return, including extensions. See Report Foreign Bank and Financial Accounts for more information on FBARs.
Also see Delinquent FBAR submission procedures and Streamlined filing compliance procedures, for more information about filing delinquent FBARs.
