Absolutely, there are several ways to do this, and you don’t have to be a metalworker to pull it off. The simplest option is a clamp-on bench table or a tray that slides over the armrest. If your bench has a flat or square armrest, look for a removable clamp-on bench table designed for wheelchairs, deck railings, or stadium seats; many of them fit urban benches too. They usually have a cup holder or a small flat surface just big enough for a coffee and a paperback.
If you want something a little more stable, consider an attachable bench tray made from weatherproof plywood or bamboo. You cut a U-shaped notch so the board rests across the armrest or over your lap, then add a small rim or groove to stop a cup from sliding. This kind of DIY bench side table is great because you can take it with you and it doesn’t damage public furniture.
For a semi-permanent solution, you can build a small folding table that bolts to the bench armrest or seat edge — but only if the bench belongs to you or you have permission from the city or property owner. In most public spaces, permanent modifications are not allowed, so clamp-on, strap-on, or weighted designs are safer.
My favorite low-effort option is a portable bench table with a beanbag or weighted base. You set it on the seat next to you, and it gives you a stable spot for a cup and a book without any hardware. Some outdoor versions even have a small lip for a phone or e-reader.
If you mainly want coffee, a bench cup holder that clamps to the armrest can be enough. If you want room for a book too, get a tray at least 10–12 inches wide. A good urban bench table should be made from weather-resistant materials like powder-coated steel, teak, bamboo, or HDPE plastic so it can handle rain and sun.
In short, yes — you can add a small table to an urban bench. Choose a non-invasive attachable or portable design, keep the surface about the size of a magazine, and you’ll have a comfortable spot for coffee and a book without damaging public furniture.