What replacement usually means, and why the range is wide
A like-for-like swap is the cheapest job on the list: same fuel, same size, same spot, with the venting, gas line or wiring already in place. Every change you make to that list adds work. A bigger tank, a different fuel, a different type of heater or a different location each moves the price, and some move it a lot.
That is why you will see one company advertise a low number and another quote far higher for what sounds like the same heater. The heater is only part of the bill. The rest is what the house needs around it to meet code and to work properly for the next ten years or more.
Like-for-like replacement: the baseline
If you have a standard 40 to 50 gallon tank in a closet, garage or utility room and you want the same thing back, this is the lowest-cost path. The old unit comes out, the new one goes in, and the existing vent, gas line or electrical connection is reused as long as it is still in good shape and up to current code.
The catch is the phrase "as long as". Old shutoff valves that will not close, a corroded gas connector, a vent that is undersized for today's unit or a missing drain pan are all found when the old heater comes out. We tell you before we fix anything, and you approve it first.
Upsizing: when a bigger tank costs more than the tank
If the household has grown, a 75 to 80 gallon tank can end the cold showers. It also costs more than the extra gallons suggest. A larger unit may need a bigger gas line or a larger breaker, and it needs more floor space and sometimes a different vent. Ask whether a second smaller heater or a different type would solve the problem more cheaply before you pay for a very large tank.
Switching type or fuel: tank to tankless, gas to electric, or a hybrid
This is where quotes spread out. Going from a tank to a gas tankless is the biggest variable on the list. A tankless unit needs new venting, a gas line sized for a much higher burn rate, and a condensate drain for a condensing model. A hybrid heat-pump heater is the most efficient electric option, but it needs open air around it and a drain for the condensate it makes.
Replacing an existing tankless with a new one is much simpler, because the venting and gas are already in place. We install Navien and Rinnai tankless units and Bradford White tanks. For a plain-language comparison of tank and tankless, see our water heater page.
If you are weighing a switch, say so when you call. The right answer depends on your hot water use, where the unit sits and what is already behind the wall, not on what is newest.
What fails at 10 to 15 years
A tank water heater typically lasts roughly 8 to 12 years, and many are well past that when they finally go. What fails is usually one of a few things. The tank itself corrodes from the inside, and once it leaks the tank cannot be repaired. Sediment builds on the bottom and makes the burner or elements work harder and the unit rumble. The temperature and pressure relief valve, the gas valve or an element can wear out and, on a younger tank, are worth replacing.
A leak at the tank body means replacement. A leak at a fitting, valve or connection might not. If your unit is 10 or more years old and the tank is wet, plan on replacing it. Moisture around the base, rusty hot water, popping or rumbling noises and running out of hot water faster than you used to are all signs it is close.
Repair or replace?
Repair makes sense on a newer unit with a single failed part: an element, a thermostat, a gas valve, a relief valve. Replacement makes sense when the tank is leaking, the unit is well past its expected life or repairs are stacking up. As a rule of thumb, a repair that costs a large share of a new heater, on a unit that is already old, is money spent on borrowed time.
If you are not sure, a diagnostic visit costs far less than replacing a heater that only needed a part, and far less than repairing one that was done for. We will tell you which one we think it is and why, and you decide.
Everything else that moves the price
Tank or tankless, gas or electric and capacity set the base. After that, venting and gas line sizing matter most, especially when a vent cannot be reused or a gas line is too small for the new unit. Code upgrades add smaller line items: a thermal expansion tank, a drain pan with a relief discharge line, correct bonding and new shutoff valves.
Location matters. A heater in a garage or closet at ground level is quicker and cheaper to swap than one in an attic, where the unit has to be carried up and the drain and pan details matter more because a leak lands on your ceiling. Removal and disposal of the old unit is part of the job. The permit and inspection fee is passed through at cost and varies by town, so we do not put a single figure on it here.
Timing matters too. A scheduled replacement lets us order the right unit and plan the work. An emergency replacement, when the tank has already failed, limits your choices to what we can get quickly. Financing, if you want it, does not change the price of the job. See financing options for how it works.