Great question—this is exactly the kind of detail that makes a public space work for everyone.
Under the ADA Standards for Accessible Design, a compliant bench seat should be between 17 and 19 inches above the ground or floor. Many urban benches fall in that range, but some are lower for style reasons or higher because of thick slats. The only way to know for sure is to measure from the ground to the top of the seat surface.
For older adults, I’d aim for the high end of that range: 18 to 19 inches. That’s close to a standard chair height, which makes it much easier to sit down and stand up without needing help. If a bench is lower than 17 inches, many seniors will struggle to rise. If it’s higher than 19 inches, shorter users may feel unstable because their feet don’t touch the ground.
But seat height is only part of ADA compliance. A truly accessible bench also needs a stable, level surface and an accessible route leading to it. Back support and armrests are not always required for every bench, but they’re strongly recommended for older users. Armrests give people something to push against when standing, and a backrest reduces fatigue. A firm, slip-resistant seat surface and rounded edges also help prevent falls.
So if you’re checking an urban bench, ask three things: Is the seat top 17–19 inches high? Is there a clear, level path to it? Does it offer armrests or a backrest for older users? If the first is yes and the second is yes, it’s generally on the right track. For senior-friendly seating, go with 18–19 inches and add arms whenever possible.
I’d still recommend checking local building codes or a licensed accessibility consultant for a final determination.