Water heaters typically last between 8 to 12 years on average, though this can vary depending on factors such as the type of water heater, quality of installation, maintenance, and water quality

. Lifespan by water heater type:

• Gas tank water heaters: about 8-12 years
• Electric tank water heaters: about 10-15 years
• Tankless water heaters: generally last longer, around 20 years or more, sometimes up to 30 years
• Heat pump water heaters: around 15 years
• Solar water heaters: about 10 years

Maintenance impact:
Regular maintenance, such as flushing the tank annually and replacing the anode rod every 3-5 years, can significantly extend a water heater's lifespan, sometimes beyond 20 years

. Signs you may need to replace your water heater:

• Age over 10-12 years
• Leaks around the base or fittings
• Rusty or discolored water
• Inconsistent water temperature or insufficient hot water
• Frequent breakdowns or noises like sizzling

In summary, while most water heaters last about 8-12 years, proper maintenance can extend their life considerably, especially for tankless models which can last 20 years or more.