Businesses accommodating people with disabilities may qualify for some of the following tax credits and deductions.

The Disabled Access Credit provides a non-refundable credit for small businesses that incur expenditures for the purpose of providing access to persons with disabilities. An eligible small business is one that earned $1 million or less or had no more than 30 full time employees in the previous year; they may take the credit each and every year they incur access expenditures. Refer to Form 8826, Disabled Access Credit, for information about eligible expenditures.

The Architectural Barrier Removal Tax Deduction encourages businesses of any size to remove architectural and transportation barriers to the mobility of persons with disabilities and the elderly. Businesses may claim a deduction of up to $15,000 a year for qualified expenses for items that normally must be capitalized. Businesses claim the deduction by listing it as a separate expense on their income tax return. Also, businesses may use the Disabled Tax Credit and the architectural/transportation tax deduction together in the same tax year, if the expenses meet the requirements of both sections. To use both, the deduction is equal to the difference between the total expenditures and the amount of the credit claimed.

Source: https://www.irs.gov/businesses/small-businesses-self-employed/tax-benefits-for-businesses-who-have-employees-with-disabilities