Del. Code tit. 13, § 2209

Within 2 business days after the date information regarding a newly hired employee is entered into the State Directory of New Hires pursuant to § 2208(b) of this title, the Division shall transmit a notice to the employer of an employee whose child support obligation is subject to enforcement by the Division directing the employer to withhold from the income of the employee an amount equal to the monthly (or other periodic) child support obligation (including any past due support obligation or retroactive support) of the employee, unless the employee’s income is not subject to withholding under § 513(b)(1) of this title and transfer the National Medical Support Notice to the employer.