Effective for tax years beginning after December 31, 2015, there are new due dates for partnership and corporation income tax returns.

Partnerships

Partnerships are now due the 15th day of the third month after the end of the fiscal year. This translates to March 15th for calendar year partnerships. This is one month earlier than under the previous law.

Partnerships can obtain an automatic six-month extension.

Corporations

Corporations are now due the 15th day of the fourth month after the end of the fiscal year. April 15th for calendar year corporations. This is one month later than under previous law.

Corporations will also be granted a six-month extension.

As usual, Congress does not make anything easy. C corporations whose fiscal year ends on June 30, do not have to follow the new due dates until tax years beginning after Dec. 31, 2025. The six-month extension does not start until 2026. Until then, calendar-year corporations will get a five-month extension while corporations with a June 30 year end will get a seven-month extension.