Delaware Code
Subchapter III. Procedure and Administration
§ 534. Failure to file tax return or to pay tax.

(a) In case of failure to file any return required under authority of this title or Title 4 on or before the date prescribed therefor (determined with regard to any extension of time for filing), unless it is shown that such failure is due to reasonable cause and not due to wilful neglect, there shall be added to the amount required to be shown as tax on such return 5% of the amount of such tax if the failure is for not more than 1 month, with an additional 5% for each additional month or fraction thereof during which such failure continues, not exceeding 50% in the aggregate. For purposes of this subsection, the amount of tax required to be shown on the return shall be reduced by the amount of any part of the tax which is paid on or before the date prescribed for payment of the tax and by the amount of any credit against the tax which may be claimed on the return.
(b) (1) In case of failure to pay the amount shown as tax on any return specified in subsection (a) of this section on or before the date prescribed for payment of such tax (determined with regard to any extension of time for payment), unless it is shown that such failure is due to reasonable cause and not due to wilful neglect, there shall be added to the amount shown as tax on such return 1% of the amount of such tax if the failure is for not more than 1 month, with an additional 1% for each additional month or fraction thereof during which such failure continues, not exceeding 25% in the aggregate. For purposes of computing such addition for any month, the amount of tax shown on the return shall be reduced by the amount of any part of the tax which is paid on or before the beginning of such month and by the amount of any credit against the tax which may be claimed on the return. If the amount required to be shown as tax on the return is less than the amount shown as tax on the return, this paragraph shall be applied by substituting such lower amount.
(2) In the case of failure to pay any amount in respect of any tax required to be shown on a return specified in subsection (a) of this section which is not so shown (including an assessment made pursuant to § 528(a) of this title) within 10 days after any assessment thereof becoming final, unless it is shown that such failure is due to reasonable cause and not due to wilful neglect, there shall be added to the amount of tax stated in the notice of proposed assessment 1% of the amount of such tax if the failure is for not more than 1 month, with an additional 1% for each additional month or fraction thereof during which such failure continues, not exceeding 25% in the aggregate. For purposes of computing such addition for any month, the amount of tax stated in the notice of proposed assessment shall be reduced by the amount of any part of the tax which is paid before the beginning of such month.
(c) (1) For tax periods beginning after December 31, 1999, if any pass-through entity required to file a return under § 1605(a)(1) of this title for any taxable year fails to file such return by the date prescribed therefor (determined with regard to any extension of time for filing) or files a return which fails to show the information required under § 1605(a)(1) of this title, such pass-through entity shall be liable for a penalty determined under paragraph (c)(2) of this section for each month, or fraction thereof, during which such failure continues (but not to exceed 5 months), unless it is shown that such failure was due to reasonable cause.
(2) For purposes of paragraph (c)(1) of this section, the amount of penalty for any month is the product of $25, multiplied by the number of persons who were members in the pass-through entity during any part of the taxable year; provided, however, that the maximum penalty for any taxable year shall not exceed $10,000.
(3) The penalty prescribed by this subsection shall be assessed against and shall be payable by the pass-through entity, and the deficiency and appeal procedures provided in §§ 521-526 of this title shall not apply; provided, however, that the Director shall mail written notice of such penalty to the pass-through entity, which may, within 60 days from the date of the mailing of such notice, institute a protest of such penalty to the Director, whose determination shall be final.
(d) (1) For tax periods beginning after December 31, 1999, if any pass-through entity fails to comply with the provisions of § 1605(a)(2) of this title, such pass-through entity shall be liable for a penalty determined under paragraph (d)(2) of this section for each month, or fraction thereof, during which such failure continues (but not to exceed 5 months), unless it is shown that such failure was due to reasonable cause.
(2) For purposes of paragraph (d)(1) of this section, the amount of penalty for any month is $25, multiplied by the number of persons who were members of the pass-through entity at any time during the tax year, provided, however, that the maximum penalty for any taxable year shall not exceed $10,000.
(3) The penalty prescribed by this subsection shall be assessed against and shall be payable by the pass-through entity and the deficiency and appeal procedures provided in §§ 521-526 of this title shall not apply; provided, however, that the Director shall mail written notice of such penalty to the pass-through entity, which may, within 60 days from the date of the mailing of such notice, institute a protest of such penalty to the Director, whose determination shall be final.
(e) This section shall not apply to any failure to file a declaration of estimated tax or to pay any estimated tax.
(f) (1) In case of each failure to file a statement of payment to another person required under the authority of this title, including the duplicate statement of tax withheld on wages, by the date prescribed therefor (determined with regard to any extension of time for filing), unless it is shown that such failure is due to reasonable cause and not due to wilful neglect, there shall be paid by the person so failing to file such statement, in the same manner as tax, a penalty of $2.00 for each such failure, but the total amount imposed on the delinquent person for all such failures during any calendar year shall not exceed $2,000.
(2) Any person required to file an information return pursuant to § 1154(i) of this title who fails to file such return on or before the date prescribed for its filing or who fails to include all the information required to be shown on the return or who includes incorrect information on the return or who fails to file in the required manner, shall unless it is shown that such failure is due to reasonable cause and not due to wilful neglect, pay a penalty in an amount equal to one half the amount specified in the Internal Revenue Code, as it may be amended from time to time, for such failure.
(g) The Director shall assess a penalty of $500 against any individual who files what purports to be a return of any tax imposed by this title or Title 4 but which:

(1) Does not contain information on which the substantial correctness of the self-assessment may be judged or contains information that on its face indicates that the self-assessment is substantially incorrect; and
(2) Evidences a position that is frivolous or a desire to delay or impede the administration of the revenue laws of this State.
(h) In the case of failure of an employer required to deposit taxes by electronic funds transfer under the provisions of § 1154(g) of this title to make transfer by such means, unless it is shown that such failure is due to reasonable cause and not due to wilful neglect, there shall be added to the amount shown as tax required to have been electronically transferred 5% of the amount or $500 per required payment, whichever is less.
(i) For tax periods beginning after December 31, 1994, with respect to any return, the amount of the addition to the tax under subsection (a) of this section shall be reduced by the amount of the addition to the tax under subsection (b) of this section for any month (or fraction thereof) to which an addition to the tax is applied under both subsections (a) and (b) of this section.
(j) If any failure to file any return is fraudulent, subsection (a) of this section shall be applied by substituting “15” for “5%” each place it appears and by substituting “75%” for “50%.”
(k) For purposes of subsection (a) of this section, reasonable cause shall be deemed established in the case of failure to file a return in the time prescribed by Part III of this title, where the taxpayer filed within the time prescribed in a written notification by the Director that the taxpayer is eligible to file returns on a basis less frequent than is actually the case.
(l) In the case of failure of any person to obtain or renew a business license required under the provisions of Part III of this title, unless it is shown that such failure is due to reasonable cause and not due to wilful neglect, there shall be added to the amount of the business license fee required to be paid a penalty in the amount of $200. Whenever a penalty has been proposed for assessment under this subsection, the Director shall not be required to issue a business license to the taxpayer to whom such assessment has been proposed unless and until the taxpayer has paid any license fee necessary for issuance of such license and has either:

(1) Paid the assessment provided under this subsection (subject to any claim for refund); or
(2) Filed a written protest regarding such assessment of penalty pursuant to § 523 of this title.
The penalty described in this subsection shall not be assessed in the instance of self-disclosure by a taxpayer of delinquency in meeting the licensing requirements of Part III. The penalty described in this subsection shall, only with respect to the same failure to obtain or renew a license and not with respect to failure to pay taxes on gross receipts or any other acts or omissions, be in lieu of the penalty described in subsection (a) of this section, except where such penalty determined under subsection (a) of this section shall exceed the penalty determined under this subsection, in which event subsection (a) of this section shall apply, and this subsection shall not apply.
(m) Any person who fails to file any return in the manner prescribed by law and required under authority of this title or Title 4 on or before the date prescribed therefor (determined with regard to any extension of time for filing), unless it is shown that such failure is due to reasonable cause and not due to wilful neglect, shall be liable for a penalty of not more than $50, in addition to any other amounts prescribed under this title that shall be assessed and collected by the Director.