Form 2350 - Application for Extension of Time To File U.S. Income Tax Return

Use Form 2350 to request an extension to file your tax return if you plan to file Form 2555 and need time to meet the bona fide residence or physical presence tests.

You may be eligible for the foreign earned income exclusion or housing deduction.
Other taxpayers should submit Form 4868, Application for Automatic Extension of Time To File U.S. Individual Income Tax Return, to request an extension to file their returns.