If you’re placing several outdoor benches in a row, the short answer is: leave at least 18–24 inches (46–61 cm) between individual benches for basic comfort, and ideally 30–36 inches (76–91 cm) if you want people to sit without brushing shoulders, bags, and knees. For accessible routes or areas where wheelchairs and strollers may pass, plan for a 36–48 inch (91–122 cm) clear gap at regular intervals or beside the row.
In practice, outdoor bench spacing depends on how the benches are being used. If separate benches are lined up end-to-end along a walkway, a 12–18 inch (30–46 cm) gap between the ends is usually enough to stop armrests from clashing and give people a small sense of personal territory. In a busy park, plaza, or schoolyard, however, I would not go below 24 inches (61 cm). That little extra distance reduces the awkward squeeze when someone sits down or stands up while someone else is already seated.
For a more comfortable social setup—like a patio, rooftop, or garden seating area—space the benches 30–36 inches (76–91 cm) apart. This gives people room to cross their legs, set down a bag or coffee, or turn toward each other without feeling packed in. If the benches have armrests or high backs, lean closer to 36 inches so the row does not feel like one long crowded bleacher.
If the benches are placed along a building, fence, or retaining wall, also consider the distance from the bench to the wall or path. Keep at least 36 inches (91 cm) of clear space in front of or behind the bench so people can walk past without brushing against knees. For ADA bench clearance, leave a 36-inch minimum clear space at one end of the row or a 48-inch space between grouped benches on a level surface so a wheelchair can pull alongside a companion bench.
Climate and maintenance matter too. In hot, sunny locations, leaving 36 inches or more between benches reduces the feeling of shared body heat and gives room for umbrellas or shade sails. In rainy or leafy areas, a slightly larger gap helps benches dry faster and makes it easier to sweep leaves, snow, or trash between units.
A simple rule I use: 18 inches is the absolute minimum between individual benches, 24 inches is the practical minimum for public areas, and 30–36 inches is the comfort zone for a row that actually gets used. If you’re unsure, go with 36 inches. It rarely feels too spacious, but it almost always solves the “too close” problem.