Yes, you can electronically file your return after April 15th, however to do so you must file Form 4868 (PDF), Application for Automatic Extension of Time to File U.S. Individual Income Tax Return, on or before April 15th. If the extension is timely filed, you have until October 15th to file your return. If April 15th falls on a weekend or federal holiday, you have until midnight the following business day to submit your extension or your tax return.