The threshold of $50,000 or $600,000 depends on whether you have foreign financial assets and either living in the U.S. or outside of the U.S.:
Form 8938, Statement of Specified Foreign Financial Assets
Specified individuals living in the US:
Unmarried individual (or married filing separately): Total value of assets was more than $50,000 on the last day of the tax year, or more than $75,000 at any time during the year.
Married individual filing jointly: Total value of assets was more than $100,000 on the last day of the tax year, or more than $150,000 at any time during the year.
Specified individuals living outside the US:
Unmarried individual (or married filing separately): Total value of assets was more than $200,000 on the last day of the tax year, or more than $300,000 at any time during the year.
Married individual filing jointly: Total value of assets was more than $400,000 on the last day of the tax year, or more than $600,000 at any time during the year.