Expats have an automatic extension of their tax filing deadine, to June 15th. They can indeed use Form 4868 to extend to Oct 15th beyond that.
I asked ChatGPT how to do this on TurboTax, and this was the response (which worked for me):
To file Form 4868 for an expat extension to October 15 in TurboTax Online:
Log in → wait for prior year data to load.
Navigate to Tax Home (this may take a few screens where they pitch you on various options. Skip them all until you get to a screen that has the Tax Home button)
Go through "Other Tax Situations".
Scroll down to the full list until you find:
💡"File an extension to get more time to file your taxes"
Indicate that you're living outside the U.S. (very important — this justifies the June 15 window).
Submit electronically.
Even though it's free, TurboTax still routes you through screens that are mostly aimed at people preparing full returns or being upsold — so it can feel like overkill for just filing Form 4868.
