Not if you filed it through the mail.
Using TurboTax Easy Extension to file a tax extensionTurboTax EasyExtension is a simple, online tool that allows you to file a tax extension in minutes. Try it here. Heads up - filing Form 4868 only provides you with an extension of time to file. You must still pay 100 percent of the tax you owe by the original April 15 deadline to avoid interest and late-payment penalties.