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In Oakton, a tankless water heater installed is $8,886 to $10,486. That’s after $500 off any size, the best water heater deal we have. Call SwiftPro, rated 5.0 stars across 1,130 reviews, at (703) 997-9757, 24 hours a day, 7 days a week.
Price range
$8,886-$10,486
8yrs @ 7.99%
$126/mo
15yrs @ 9.99%
$95/mo
Monthly figures on the starting price, the whole price financed, on approved credit. The lender sets the final terms. How financing works
We install in Oakton under Virginia Class A contractor license 2705192276, and SwiftPro is rated 5.0 stars across 1,130 reviews. Tankless water heaters in Oakton, 22124: where the gas line exists, where it doesn’t, and what the 1980s and 90s houses around Difficult Run need. Staying with a gas tank on the flue you have is $3,238 to $5,485. Once a year a tankless wants a descale, $300 right now, regularly $350.
5.0 stars across 1,130 reviews
One of our plumbers at a wall-hung tankless unit, the condensate line and the PVC vent in view.
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Licensed and insuredVirginia Class A contractor #2705192276
24/7 emergency serviceWe answer day or night, and we will tell you honestly when we can get there.
Our own plumbers, our own trucksNobody here is a subcontractor with a magnet on the door
The price is settled before the workYou see the number in writing before anything is taken apart
What it costs
Installed, from the same price book as our water heater estimator: the unit, the gas line work it needs, the new venting, the condensate drain, the permit and hauling the old tank away.
Tankless water heater, installed
$8,886 to $10,486
or $148/mo at 0% APR for 60 months
Gas or propane tank on the flue you have, installed
$3,238 to $5,485
or $54/mo at 0% APR for 60 months
Tankless descale, with the plumbing check
$300, regularly $350
Monthly figures: 60mo @ 0% APR on each starting price, the whole price financed, on approved credit. Longer plans lower the payment and cost more in total. The lender sets the final terms. How financing works
Prices checked .
Where you land in the range is mostly the gas line. A tankless burner fires far harder than a tank’s, so an older line sized for a tank often has to be upsized from the meter. We look before we quote, so that’s in the number, not a surprise.
A tankless unit’s heat exchanger scales up in hard water, so it wants a descale every year: $300 right now, regularly $350. We’ll show you the inlet screen and what came off it.
What’s different in Oakton
Only about half of Oakton homeowners heat with gas, 48.5 percent by the Census count, and over 42 percent use electricity. That is a lower gas share than most of the towns we serve, and it decides everything. A house with no gas line almost always stays with a tank, because an electric tankless asks for more from your panel than most panels have to give. We will tell you that on the phone and save you a visit.
Propane tankless exists, and about four percent of Oakton homeowners are on propane. If you have a tank in the yard already, a propane tankless is a real option, with its own gas regulator and a vent through the wall. It is a smaller group of houses, but they get a real answer rather than a flat no.
Where there is gas, the typical Oakton house is a detached one. Close to two thirds of homes in 22124 are, and nearly half went up between 1980 and 1999. Those houses were piped with a bit more room, and the water heater often stands in a basement against an outside wall. That makes for a short PVC run and a quick job. The tank is probably the second one the house has had.
Difficult Run is nearly all detached houses, mostly from the 70s and 80s, on bigger lots than most of Fairfax County. Space is not the issue there; the vent has plenty of wall to choose from. The thing to settle is how far the water heater sits from where hot water gets used. A long run to a far bathroom or a master suite means a wait at the tap, and a recirculation loop, which we can add, changes that.
Neighborhood by neighborhood
Census figures for the owner-occupied homes in each place, and what usually decides a tankless job in houses like them.
| Place | Median home built | Most homes are | Heated with | What usually decides the job |
|---|---|---|---|---|
| Oakton | 1981 | single-family houses, about 4 in 10 | gas, about 6 in 10 | A short PVC vent out the basement wall. |
| Difficult Run | 1982 | single-family houses, nearly all | gas, about 6 in 10 | A short PVC vent out the basement wall. |
By the numbers
From the Census Bureau’s 2020 to 2024 survey. Median year built and heat count owner-occupied homes only.
ZIP 22124 as a whole: every Oakton address. The Oakton Census place in the table also takes in streets with Vienna and Fairfax mail.
Is it worth it
In a big Oakton house the tank is often at one end and the tub at the other. Waiting for hot water while the cold runs down the drain is the thing people tire of first, and it is worth raising before the tankless is sized.
When two showers and the dishwasher empty the tank before everyone’s done, a tankless heats as you use it. It won’t run dry, but it has a flow limit, so it’s sized to how many taps run at once.
A tankless unit hangs on a wall about the size of a carry-on bag. Where a 50 or 75 gallon tank took a corner of the utility room, the floor under it is yours again.
Need tankless water heaters in Oakton?
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Choosing who installs it
Questions to ask anybody who quotes you a tankless, us included.
In Oakton, nearly half of homes do not have gas. An installer who quotes a gas tankless without asking is either guessing or planning to run a new line. Ask which.
A tankless burner can draw several times what a tank does. A quote written without checking the line from the meter is a quote that grows on install day.
What matters is how many showers and faucets run at the same time, and how cold the water comes in during winter. Ask what flow rate they sized it for and why.
Two of our crew going over a work order before the day's calls.
From our Google reviews
5.0 stars across 1,130 reviews. Read them on our reviews page.
This Company installed a tankless water system!!! They were great!!! Very Professional & Efficient & they Cleaned up & took out the old water tank! I would highly recommend them!!
Questions
Usually not worth it. A whole-house electric unit needs a heavy circuit most panels cannot spare. A tank is the sensible choice unless you have gas or propane.
If it has gas and a wall to vent through, yes. Most are inside units, which makes the vent the tight spot. We check the wall before we quote.
Installed, $8,886 to $10,486, with the gas line work, the venting, the condensate drain and the permit in that number. A gas tank on the flue you have is $3,238 to $5,485, so the gap is what you pay for the floor space and the hot water that keeps up.
It never empties, because there’s no tank to empty. It does have a limit on how much hot water it makes per minute, and in January, when the water comes in cold, that limit drops. Sized to the number of showers you run at once, a family doesn’t notice.
Ready when you are
Call, or send the form at the top. We look at the gas line, the wall it would vent through and how much hot water you run at once, and you get the price in writing before anything comes out.
SwiftPro Heating, Cooling & Plumbing
4230 Lafayette Center Dr N, Chantilly, VA 20151
44679 Endicott Dr, Suite 211, Ashburn, VA 20147
SwiftPro Plumber & Water Heaters
4200 Lafayette Center Dr, Suite N, Chantilly, VA 20151
Virginia Class A contractor license #2705192276
SwiftPro Heating, Cooling & Plumbing is a licensed, BBB Accredited (A rating), independently owned heating, cooling and plumbing company in Chantilly, serving Oakton and the rest of Northern Virginia. Virginia contractor license #2705192276. 5.0 stars across 1,130 reviews on Google, Angi, Yelp, the BBB and Facebook. SwiftPro maintains a dedicated HVAC team and a dedicated plumbing team.
From SwiftPro Heating, Cooling & Plumbing in Chantilly. Housing figures are the Census Bureau’s American Community Survey, 2020 to 2024, for each place named; permit, water and sewer facts link to each office’s own page and were checked in September and October 2026.