The best way really depends on two things: whether you're allowed to drill into the concrete, and how permanent you want the anchor to be. For most urban patios, I'd go with stainless steel wedge anchors for permanent installations, or epoxy-set anchors if you need maximum holding power or the concrete is a bit questionable. If you rent or can't drill, use weighted bases and security cables instead.
First, check the furniture and the slab. Look at the feet or base plates. Most benches, tables, and planters either have pre-drilled holes or can accept a surface-mounted bracket. Make sure the concrete is at least 3 inches thick—more if the furniture is tall or catches wind. Avoid drilling near cracks, expansion joints, or hidden conduits. If it's a shared roof deck or leased patio, get permission first.
For permanent anchoring, wedge anchors are the gold standard. Use 3/8-inch or 1/2-inch stainless steel wedge anchors, depending on the load. Drill a hole with a hammer drill and the exact carbide bit size, going about 1/4 inch deeper than the anchor. Vacuum or blow out the dust—this matters more than people think. Hammer the anchor in, add a washer and nut through the furniture's base plate, and torque it down. For extra security, use tamper-resistant nuts or a thread-locking compound.
If the furniture is lighter—say a small side table or a chair you don't want to blow away—concrete screws like Tapcons can work. They're faster and leave a smaller hole, but they don't have the same pull-out strength. Use them with a plastic or metal sleeve if the concrete is older or crumbly.
For heavy-duty or high-theft areas, epoxy-set threaded rods are excellent. Drill, clean, inject two-part epoxy, and insert the rod. Once cured, bolt the furniture down with security nuts. Drop-in anchors are another option; they sit flush when not in use, which is nice if you sometimes remove the furniture. Just remember that epoxy and drop-in anchors need clean, dry holes and the right curing time.
If you can't drill, don't panic. Weighted bases are the practical answer. Use sand- or water-filled bases, heavy planters, or ballast boxes. For umbrellas, use a proper weighted umbrella base rated for wind. You can also connect furniture to a cable lock or chain anchored to a wall, post, or existing railing—but make sure the structure can handle it. Avoid relying on outdoor adhesive alone; sun, rain, and temperature swings will eventually weaken it.
A few urban-specific tips: use stainless steel hardware, not zinc-plated, because it survives weather and cleaning chemicals. Add nylon washers between dissimilar metals to reduce galvanic corrosion. Seal the anchor hole with a little exterior-grade silicone if water pools there. And check the anchors twice a year—urban patios get wind, snow, and heavy use.
So, the short answer: for a solid concrete patio and furniture you want to stay put, use stainless steel wedge anchors with base plates. For maximum security or tricky concrete, use epoxy-set anchors. For rentals or no-drill situations, use weighted bases with a security cable. That combination covers almost every urban patio situation.