The Online Easy Extension program requires a U.S. address in order to process your extension electronically.
If you have a U.S. address that you can use, then you can just use that address (you can file your actual return with a different address, i.e. your foreign address). Otherwise, you can paper file an extension form using the form below. It is a very simple form to fill out and you can write in your foreign address.
You can also electronically file an extension using the IRS Free Fillable Forms - you will have to create an IRS account and go through the filing process with them, but you can indicate a foreign country on this form and electronically file. Note: You will need to choose the option for income over $66,000 even if that doesn’t apply.
You also may qualify for an automatic two-month extension but reason of being out of the country, but you would need to use TurboTax desktop software to attached the requirement statement when you file your actual return.