Alaska Filing Due Date: Corporate tax returns are due within 30 days of the Federal filing deadline (which is March 15 for calendar year filers). This means that most Alaska corporations must file by April 15. However, full payment of your Alaska tax is due by the 15th day of the 3rd month following the end of the taxable year.
Extended Deadline with Alaska Tax Extension: With an extension, Alaska corporate returns are due within 30 days of the Federally extended deadline (which is September 15 for calendar year filers). This means that an Alaska extension will give you until October 15 to file.
Alaska Tax Extension Form: There is no application to request an Alaska extension. But if you owe Alaska tax, you should use the voucher on Form 6240 to remit payment.
Alaska Extension Payment Requirement: An extension of time to file is not an extension of time to pay. Your Alaska tax liability must be paid by the original due date to avoid penalties. You can make an Alaska extension payment using Form 6240. Extension payments of $150,000 or greater should be made electronically via the Online Tax Information System.
Alaska Tax Extension Tip: If you have filed a valid Federal Business Tax Extension, you will automatically receive an Alaska tax extension.