Water heater replacement costs $600 to $3,100. Tankless water heater installation costs $1,400 to $5,600. A new standard tank water heater costs $400 to $2,100 for the unit, plus $200 to $1,000 for the installation labor.

Tank hot water heaters last 8 to 15 years on average. Tankless water heaters last 10 to 20 years on average.

Signs a water heater is going out:

• Rusty, discolored, or metallic-tasting water
• Loud clanging, knocking, gurgling, or whining noises
• Hot water that runs out quickly
• Low water pressure
• Foul odor coming from hot water
• Low or irregular water temperature, or no hot water at all
• Leaks at the base of the tank or around the pipes at the top of the tank

Most cities require a permit to install a water heater. A water heater permit costs $50 to $200 on average. Most plumbers pull the permit and include permit fees in their estimate.

Manufacturer warranties and local building codes may require a water heater permit and installation by a licensed plumber. Installing a water heater yourself is possible but requires plumbing and electrical experience.

Installing a tank water heater takes 2 to 6 hours, depending on accessibility. Tankless water heater installation takes 3 to 10 hours for a new install or 2 to 4 hours to replace an existing tankless unit. Replacing a water heater in an attic, closet, or other tight space increases the labor time.

Licensed plumbers install tank and tankless water heaters, including gas, electric, and hybrid heat pump systems. Home Depot and Lowe's also offer water heater installation through their network of licensed plumbers.

Gas water heaters cost $100 to $700 more than electric up front, but cost $220 less per year to operate. Electric water heaters are cheaper to replace than gas and last 2 to 3 years longer, but cost more to operate.

Finding reputable contractors requires planning, researching, and asking questions. To hire the best:

• Get at least three estimates from plumbers to compare.
• Look for plumbers with experience installing tank or tankless water heaters.
• Select companies that are licensed, insured, and bonded.
• Check out their reviews and previous work on HomeGuide and Google.
• Make sure the quote includes removal of the old water heater.
• Ask about their guarantees.
• Get an itemized estimate, contract, and warranty in writing before the work begins.
• Avoid making payments upfront. Pay after installation is completed.

When looking to hire a gas water heater installer near you, ask them the following questions:

• Do you recommend a tank or tankless water heater for my needs, and why?
• What size water heater do I need for my home?
• Which type of water heater do you have the most experience installing?
• Would a gas, propane, or electric water heater be best for my home, and why?
• Would my home benefit from a hybrid heat pump water heater, and why?
• Which water heater brands do you offer, and why do you recommend those brands?
• Are there any manufacturer rebates available?
• Does your estimate include removing and disposing of the old water heater?
• What additional costs should I expect?
• What permits do I need, and will you obtain them?
• How long will the installation take?
• How long is the warranty, and what does it cover?
• How long will the water heater last, and what can I do to make it last longer?
• What kind of maintenance will my new water heater require?
• What payment methods do you accept?
• What do I need to provide to get started?