Corporate Income Tax

State Corporate Income Tax is one of the central taxes collected from the business by the State of Delaware. In principle, every domestic or foreign corporation doing business in Delaware, saving certain exemptions under the law, is liable to file a tax return irrespective of the amount of income earned. Taxpayers are required to register corporate income tax returns, including attachments, in paper form. As to the tax rate of this tax, it is, in principle, 8.7% on its federal taxable income allocated and apportioned to Delaware.

The due date for filing this type of corporate income tax return is on or before April 15 of the following year for calendar year taxpayers. In terms of fiscal year taxpayers, the due date is on or before the 15th of the fourth month following the close of the fiscal year. On the other hand, the due dates might also be extended depending on the circumstances Federal extensions the state owing dates as well. However, please note that the extension of time to file does not mean an extension of time to pay.

Please note that any late filing and payment of withholding tax will result in penalties. Any late filing is subject to a penalty of 5% per month, plus interest of 0.5% per month from the original due date until paid. Failure to pay is also subject to an additional penalty of 1% per month, though not to exceed 25%.


– During the filing process of Delaware Corporate Income Tax, you are required to attach a completed copy of the corporation’s FEDERAL income tax returns, including all schedules and attachments.

– State of Delaware recognizes the federal S categorization. Consequently, S-Corporations that generate income from sources within Delaware are required to file a Form 1100S, S-Corporation Reconciliation, and Shareholders Information Return.

– Companies that enjoy exemption statuses do not have to file a Delaware corporate income tax return. However, this exemption does not preclude companies from filing the required annual report with the Delaware Division of Corporations.
– To be paid in four installments: 

1) The half (50%) is to be paid on or before the first day of the fourth month of the taxable year
2) 20% is to be paid on or before the 15th day of the sixth month
3) 20% is to be paid on or before the 15th day of the ninth month
4) 10% is to be paid on or before the 15th day of the twelfth month