Illinois' NICU Leave Law Is Now in Effect — Is Your Payroll Team Ready?
A significant new employee leave entitlement is now on the books in Illinois, and payroll departments that aren't prepared could find themselves out of compliance fast. Illinois' Family Neonatal Intensive Care Leave Act took effect on June 1, granting employees whose newborns are admitted to a neonatal intensive care unit (NICU) the right to take unpaid, job-protected leave. While the law is rooted in compassion for families navigating one of the most stressful medical experiences imaginable, its practical implications for payroll are immediate and concrete.
From determining which coverage tier applies to your organization, to coding leave correctly and managing benefits during an unpaid absence, payroll teams have real administrative work ahead. Here's a comprehensive breakdown of everything payroll professionals need to understand before processing a single NICU leave request.
What Is the Family Neonatal Intensive Care Leave Act?
The Family Neonatal Intensive Care Leave Act is Illinois' newest addition to its growing body of employee leave protections. The law specifically covers employees who have a child receiving care in a neonatal intensive care unit — a situation that often arises unexpectedly and can last days, weeks, or even months. Recognizing the emotional and physical toll this places on parents and caregivers, Illinois lawmakers created a dedicated leave category to protect these workers' jobs while they support their newborns.
The leave is unpaid by default, but it is job-protected, meaning employers cannot terminate or retaliate against an employee for taking it. That protection alone makes accurate payroll tracking essential — any misstep in documentation could expose an employer to legal liability.
Coverage Tiers: Which Employers Are Covered?
The first thing payroll needs to confirm is whether the organization is covered by the law and, if so, under which tier. The Act applies to employers with 16 or more employees in Illinois, but the amount of leave owed depends on company size.
- Employers with 16 to 50 employees are required to provide up to 10 days of NICU leave per qualifying event.
- Employers with 51 or more employees are required to provide up to 20 days of NICU leave per qualifying event.
These tiers matter enormously from a payroll administration standpoint. Before any leave is coded or any employee is notified of their entitlement, payroll and HR must confirm which tier applies. Miscommunicating the number of available days — either over-granting or under-granting — can lead to compliance failures or employee disputes. Organizations near the 50-employee threshold should pay particular attention, especially if headcount fluctuates seasonally or due to part-time staffing.
The 4 Payroll Essentials for NICU Leave Administration
Once eligibility and tier coverage are established, payroll teams need to manage four core areas carefully. Each has distinct administrative, coding, and recordkeeping components.
1. Code the Leave as Unpaid From the Start
NICU leave under this law is unpaid. There is no automatic wage replacement triggered by an employee's qualifying absence. That means payroll should code NICU leave with the appropriate unpaid leave designation from the first day — not retroactively adjust it later. Coding it incorrectly as paid leave from the outset creates a complicated correction trail and may result in overpayments that are difficult to recover.
Creating a dedicated pay code specifically for Illinois NICU leave is a best practice. It ensures clean reporting, simplifies audits, and makes it straightforward to distinguish this leave category from other absence types in your payroll system.
2. Handle Voluntary Paid Leave Substitution Carefully
While the default is unpaid, employees have the option to substitute accrued paid leave — such as vacation, sick time, or PTO — for some or all of the NICU leave period. This is an employee election, not an employer mandate. Employers cannot require employees to exhaust their accrued paid leave before or during NICU leave.
If an employee does elect substitution, payroll must apply the correct pay codes for those specific days, reduce the employee's applicable paid leave balance accurately, and ensure the overall leave period is still tracked and documented as NICU leave. The substitution is a payment mechanism, not a reclassification of the leave type itself. Maintaining that distinction in your payroll system is critical for accurate recordkeeping.
3. Maintain Benefits During the Unpaid Leave Period
Employers are required to maintain the employee's benefits throughout the duration of their NICU leave. This is a common requirement across many protected leave laws, but it introduces a specific payroll challenge: how do you collect employee-paid benefit premiums when there's no paycheck to deduct from?
Payroll teams should work with HR and benefits administrators ahead of time to establish a clear process. Options may include arrangements for employees to pay their share of premiums directly during the leave period, or deferring premiums to be collected upon return. Whatever method is used, it must be communicated clearly to the employee before leave begins and documented thoroughly in the employee's record.
4. Track NICU Leave Separately From FMLA
This is perhaps the most nuanced payroll requirement under the new law. Illinois NICU leave does not run concurrently with federal Family and Medical Leave Act (FMLA) protections in most cases — it functions as a supplement. Employees who are eligible for FMLA must exhaust their FMLA entitlement first. Illinois NICU leave then follows if the child remains in the NICU after FMLA has been used.
That sequential structure means payroll systems must track the two leave types independently. An employee might have 12 weeks of FMLA followed by up to 20 days of Illinois NICU leave — and those days must be logged, coded, and reported separately. Conflating the two not only risks compliance violations under both state and federal law but also muddles the employee's remaining entitlements.
Why Getting This Right Matters Now
With the law already in effect, there's no grace period left. Any employee with a child currently in a NICU may already be entitled to this leave. Payroll departments that haven't yet updated their systems, created appropriate leave codes, and briefed their teams are already behind the curve.
The good news is that the administrative framework is manageable once the four key areas are addressed. Review your employee headcount tier, establish clear coding protocols, set up a benefits premium collection process for unpaid periods, and build a tracking system that keeps NICU leave separate from FMLA. Done right, compliance with Illinois' Family Neonatal Intensive Care Leave Act is both achievable and sustainable — and it ensures that employees facing one of life's hardest moments receive the job protection the law intends.