Undue hardship: when an employer can say no to an accommodation

"Undue hardship" is the main legal limit on an employer's duty to accommodate a disability. Under the federal Americans with Disabilities Act (ADA) and the New York State regulation, it means significant difficulty or expense.⁠^[1][7] Under the New York City Human Rights Law (NYCHRL), an accommodation counts as reasonable unless it causes undue hardship in the conduct of the employer's business, and the employer has the burden of proving that it does.⁠^[2]

This page covers the meaning of the term under each law, the factors, who carries the burden, and the other grounds on which an employer may lawfully decline a request.

How does each law define undue hardship?

	Federal (ADA)	New York State Human Rights Law (NYSHRL)	New York City (NYCHRL)
Definition	An action requiring significant difficulty or expense, considered in light of the statutory factors.⁠[1]	The regulation defines it as significant difficulty or expense to the employer.⁠[7]	Built into the definition of reasonable accommodation: such accommodation that can be made that does not cause undue hardship in the conduct of the business.⁠[2]
Cost factor	The nature and cost of the accommodation.⁠[1]	The nature and cost of the accommodation, including any money available from other sources to help the employer pay for it.⁠[7]	The nature and cost of the accommodation.⁠[2]
Size and resources	The financial resources, workforce size and operations of the facility involved, and the overall financial resources, size, and number, type and location of facilities of the employer.⁠[1]	The overall size of the business with respect to number of employees, number and type of facilities, and size of budget.⁠[7]	The resources, workforce and operations of the facility, and the overall resources and size of the entity.⁠[2]
Type of operation	The type of operation, including workforce composition and the relationship of the facility to the employer.⁠[1]	The type of operation, including the composition and structure of the workforce.⁠[7]	The type of operation.⁠[2]

Each list turns on the particular employer: its size, its resources and the kind of operation it runs.⁠^[1][7][2]

Who has to prove it?

The answer differs by layer.

• Federal. The ADA makes it discrimination not to accommodate "unless such covered entity can demonstrate" that the accommodation would impose an undue hardship.⁠^[8] Before that question is reached, an ADA plaintiff in the Second Circuit bears the burden of showing that some accommodation existed that would allow performance of the essential functions of the job.⁠^[9]
• New York State. The NYSHRL definition of reasonable accommodation carries the proviso that the action not impose an undue hardship.⁠^[10] The statute says it does not require accommodations "which can be demonstrated to impose an undue hardship," without saying in terms who makes the demonstration.⁠^[11] The Court of Appeals, New York's highest court, has said that at trial on a NYSHRL claim the employee has to prove that a reasonable accommodation existed.⁠^[4]
• New York City. The NYCHRL says in its text: "The covered entity has the burden of proving undue hardship."⁠^[2] The Court of Appeals has described this as "contrary to the State HRL."⁠^[3] The NYC Commission on Human Rights says all accommodations are presumed reasonable unless the employer shows undue hardship, and that the evidence is assessed by a preponderance of the evidence standard.⁠^[12]

The Commission's December 2025 guidance spells out the practical effect under the NYCHRL: the law imposes no requirement on employees to prove that an accommodation is necessary or that it does not pose an undue hardship.⁠^[13] A common mistake is to assume that the employee always has to prove that a workable accommodation existed. That describes the ADA as applied in the Second Circuit and a NYSHRL claim at trial, not the NYCHRL.⁠^[9][4][2]

What does the NYC Commission expect from an employer that claims hardship?

The NYC Commission on Human Rights, which enforces the NYCHRL, gives more detail than the statute. It says an employer cannot refuse to provide an accommodation just because it involves cost, and has to consider its overall resources, outside resources and tax incentives.⁠^[5] An employer that asserts undue hardship based on financial cost "will be expected to disclose to the Commission financial documents" so that the claimed hardship can be assessed.⁠^[5] The Commission also recognizes limits: under the NYCHRL an employer is not required to substantially change its business processes or take extraordinary financial measures.⁠^[5]

The Commission applies the same approach to particular kinds of requests:

• Remote work. The mere fact that the employee would be working outside the physical office some or all of the time generally will not be sufficient to support an undue hardship defense under the NYCHRL.⁠^[14]
• Leave. Leave as a reasonable accommodation under the NYCHRL includes the right to return to the original position where keeping that job open does not cause an undue hardship; if it does, the employer has to consider alternatives that let the employee return in a different position.⁠^[15]
• Service animals. Employers covered by the NYCHRL are required to make exceptions to "no pet" policies for employees who rely on service animals unless that would cause undue hardship, and incidental property damage usually is not undue hardship.⁠^[16]

Is any accommodation off the table from the start?

Leave with no end date is the example the courts have addressed. The U.S. Court of Appeals for the Second Circuit has said the ADA's duty to accommodate does not require an employer to hold an injured employee's position open indefinitely.⁠^[17] The Court of Appeals has held that indefinite leave is not considered a reasonable accommodation under the NYSHRL.⁠^[3] In the same decision it said that under the NYCHRL it is the employer's burden to prove undue hardship, and it held that the employee's NYCHRL claim should not have been dismissed.⁠^[3][18] The Commission's guidance says there is no accommodation, "whether indefinite leave, workstation or workplace changes, or providing specific equipment," that is categorically excluded under the NYCHRL.⁠^[15] More on this is in medical leave as an accommodation.

The State regulation draws one more line for short-term conditions. For a temporary disability, the NYSHRL requires no more than de minimis accommodations in worksite accessibility, equipment, job restructuring or support services, though it may require modified schedules, reassignment to an available position or available light duty.⁠^[19]

What other reasons can an employer lawfully give?

Undue hardship is not the only ground for declining a request. Each of the following is a separate question with its own rule.

Ground	Rule
The person cannot do the essential job duties even with accommodation	Under the ADA, protection extends to a "qualified individual" who can perform the essential functions with or without reasonable accommodation.⁠[20] Under the NYCHRL, this is an affirmative defense that the employer has to prove.⁠[4]
Direct threat	The ADA defines a direct threat as a significant risk to the health or safety of others that cannot be eliminated by reasonable accommodation, and the EEOC's regulation calls for an individualized assessment of the person's present ability to safely perform the essential functions of the job.⁠[21] The State regulation says accommodation is not required where the disability or the accommodation itself poses a direct threat.⁠[22]
Seniority systems	Under the ADA, a requested accommodation that conflicts with the rules of a seniority system is ordinarily not reasonable, unless the employee shows special circumstances.⁠[23] The NYC Commission says reassignment does not require violating a bona fide seniority system or collective bargaining agreement.⁠[24]
Personal items and new positions	The State regulation excludes personal care needs and non-work-related aids such as a personal hearing aid or wheelchair, and does not require creating a completely unique position.⁠[25]
Conduct standards	The State regulation says the NYSHRL does not require accommodating behavior that fails workplace standards consistently applied to all similarly situated employees, although reasonable and necessary deviations from dress codes, grooming standards and attendance policy must be allowed.⁠[26]
A different effective accommodation was offered	The State regulation gives the employer the right to select which reasonable accommodation will be provided, so long as it is effective in meeting the need.⁠[27] Under the ADA, the Second Circuit has held that an accommodation already provided or offered that is "plainly reasonable" on the undisputed record ends the analysis.⁠[28]

The line between essential and marginal duties, and who decides it, is covered in reasonable accommodation: what an employer has to do. Scheduling and telework disputes are covered in remote work, schedule changes and reassignment.

What has to happen before an employer says no?

Under the NYCHRL, a determination that no reasonable accommodation would enable the person to satisfy the essential requisites of the job may only be made after the parties have engaged, or the employer has attempted to engage, in a cooperative dialogue, and the employer then has to provide a written final determination.⁠^[6] The Commission says the dialogue continues until an accommodation is provided or the employer reasonably concludes that none is available without undue hardship.⁠^[29]

Under the NYSHRL, the Court of Appeals has said an employer generally cannot win summary judgment unless it shows it engaged in a good-faith interactive process that assessed the employee's needs and the reasonableness of the accommodation requested.⁠^[30] Under the ADA, an employer that demonstrates good-faith efforts, in consultation with the employee, to identify and make a reasonable accommodation is protected from compensatory and punitive damages in an accommodation case.⁠^[31] These rules are explained in the interactive process and the cooperative dialogue.

If you are told "undue hardship"

For an employee, practical next steps are to ask for the reason in writing, to ask which alternatives were considered, and to propose a lower-cost or temporary option if one would work. For an employer, the practical point is to record the specific cost or operational problem and the alternatives that were explored, since each law's factors are specific to the business.⁠^[1][7][2] Steps for the request itself are in how to request an accommodation; the defenses employers raise more generally are in what employers argue; and the section as a whole starts at the disability discrimination overview.