Standard tank water heaters are rated for 10–12 years by manufacturers. In Las Vegas, without regular maintenance, that lifespan drops to 6–8 years due to our extreme water hardness. With consistent annual maintenance (flushing, anode rod replacement, professional inspections), you can often get 10+ years from a tank unit. Tankless water heaters are rated for 15–20 years but require annual descaling in Las Vegas to maintain performance.