According to the IRS:

"No, reverse mortgage payments aren't taxable. Reverse mortgage payments are considered loan proceeds and not income. The lender pays you, the borrower, loan proceeds (in a lump sum, a monthly advance, a line of credit, or a combination of all three) while you continue to live in your home.

• With a reverse mortgage, you retain title to your home.
• Depending on the plan, your reverse mortgage becomes due with interest when you move, sell your home, reach the end of a preselected loan period, or die.
• Interest (including original issue discount) accrued on a reverse mortgage isn't deductible until you actually pay it (usually when you pay off the loan in full). Also, a deduction of interest may be limited because a reverse mortgage generally is subject to the limit on home equity debt, which is not deductible unless the proceeds are used to buy, build, or substantially improve the home that secures the loan. For information on deducting mortgage interest and the debt limit that applies, see Publication 936, Home Mortgage Interest Deduction."

https://www.irs.gov/faqs/other/for-senior-taxpayers/for-senior-taxpayers