Replacing just one window: what it costs and when it makes sense

Replacing a single window usually costs about $600 to $1,800 in 2026, installed, for a standard double-hung or slider. That is more per window than you would pay in a ten-window job, because the visit, the setup, the trim work and the cleanup are the same whether we replace one window or several. Replacing one window is still a perfectly normal job. It is often the smartest first step when one window has failed and the rest are fine.

Lower Merion TwpOct 2025

Why one window costs more per unit

When a crew replaces ten windows, the cost of getting to your house, setting up, protecting floors and cleaning up is spread over ten units. With one window, all of it lands on that one. Manufacturers also price small orders a little higher, and delivery or pickup of a single unit costs the same as several.

These ranges come from 2026 national cost guides. Your price depends on the window, the wall and what we find when the old one is out.

When replacing one window makes sense

• One window has failed and the others are in good shape. A fogged or cracked unit, a broken frame or a rotted sill on a single window is a good reason to replace just that one.
• Storm or impact damage to one window.
• A remodel in one room, like a bathroom or kitchen, where the window needs to change size or move.
• A bedroom egress window that does not meet code for escape.
• Budget phasing, starting with the worst window or the weather side of the house.

When it does not

• Most windows are near the end of their life. Then the per-window savings of doing them together usually win.
• You want them to match exactly and the current windows are discontinued.
• The frame is fine and only the glass has failed. A glass unit or sash replacement can cost less than a whole window. See below.

Repair before you replace

Before replacing one window, check whether a repair will do:

• Fogged glass. The sealed glass unit can often be replaced on its own, keeping the frame and sash.
• Broken balance or sash cord. The sash will not stay up. Balances and cords are cheap parts.
• Drafts. New weatherstripping and a properly adjusted lock can fix a drafty but sound window.
• Small sill rot. Epoxy repair can save a sill with a small soft spot. Our rotted window sill guide explains when that works.

If the frame is rotted, the window is warped, or several of these problems happen together, replacement is usually better value.

Matching the rest of the house

The biggest question with one window is how it will look next to the others. Things to match:

• Brand and product line, if they are still made.
• Exterior color. White is easy. Tan, clay and dark colors vary between brands.
• Grille pattern, the number and layout of the divided lites.
• Sightlines, the width of the frame and sash you see from inside and out.
• Interior finish, painted, stained or vinyl.

If the original windows are discontinued, we look for the closest match in frame width and grille pattern. Most people cannot tell from the street when the color and grilles match.

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Masonry and older walls

One window in a brick or stone wall gets the same care as a whole house of them. On the brick house in the Douglassville area, each new window sits on a stone sill with fresh caulk to the brick, sized to its own opening.

Douglassville areaSep 2025

In old plaster rooms, we take the interior casing off carefully so it can go back, or we replace it with new casing that matches.

How one window is replaced

1. Protect the floor and furniture inside and the plants outside.
2. Remove the old sash, or the whole old frame for full-frame.
3. Check the sill and framing for rot and repair it.
4. Flash the opening, with a sloped sill pan at the bottom.
5. Set the new window level, plumb and square, and fasten it.
6. Insulate the gap with low-expansion foam or backer rod.
7. Flash the sides and head, then trim outside.
8. Trim inside, caulk and clean up.

Most single windows are done in a few hours. Full-frame in masonry or plaster can take most of a day.

Combining with other small jobs

Because the setup cost is the same, a single-window visit is a good time for other small jobs: a rotted piece of trim, a sticky door, a soft section of fascia, a new storm door. Asking for them together in one estimate usually saves money compared to separate visits.

Bathroom and stair windows

Windows next to a tub or shower, in a stair landing or near a door often need tempered glass by code. Bathroom windows may need privacy glass. Both add to the price of a single window and are worth asking about at the estimate.

Egress windows

If the window is in a bedroom, it may need to meet escape and rescue rules: a minimum net clear opening of about 5.7 square feet, a minimum opening height and width, and a sill no higher than 44 inches off the floor. Replacing a bedroom window with a smaller one can make the room non-compliant. Making the opening larger to meet code is a bigger job and may need a permit.

Contracts in Pennsylvania

Even a single window is home improvement work. In Pennsylvania, any home improvement contract over $500 must be in writing to be enforceable against the homeowner, and you have three business days after signing to cancel. Ask for the brand, model, size, glass and installation type in writing.

Picture windows and fixed glass

A single large picture window is one of the most common one-window jobs we see, often in a living room facing the yard. Because the glass is big, the price depends heavily on size and glass type. Large fixed units are heavy and usually need two or three people to set. Many owners add operable windows on each side, or choose a casement next to a fixed unit, so the room still gets air.

If the old picture window is single-pane and sweats in winter, a new unit with Low-E double-pane glass makes a big difference in comfort at that end of the room.

What to ask before you buy one window

• Is the original brand and line still made, and in my color?
• Will the grille pattern match the windows next to it?
• Insert or full-frame, and why?
• What happens if the sill or framing is rotted?
• Is interior and exterior trim included, and will it match?
• How long until the window arrives?
• Is it tempered or egress, if it needs to be?

Insert or full-frame for one window

The same choice applies to one window as to a whole house. An insert slides into the old frame and is quicker. A full-frame replacement takes the window back to the rough opening, which lets us fix a rotted sill, flash the opening properly and keep the glass area. For a single window that has failed because of water, full-frame is usually the right choice, since the water damage is often in the frame and sill, not just the sash. Our guide on insert versus full-frame replacement explains how to tell which one your window needs.

Questions people ask about replacing one window

Can you replace just one window? Yes. It is a normal job for us. The per-window price is higher than in a large job, and the work is the same.

Will one new window look different from the others? It can, if the color, grilles or frame width differ. We match as closely as the products allow, and in most cases the difference is hard to see from outside.

Is it worth replacing one window at a time? It is worth it when one window has failed or when the budget needs phasing. For a house where most windows are due, doing them together saves money.

How long does it take to get one window? Stock sizes can arrive in a week or two. Custom sizes and colors often take four to eight weeks.

Is the estimate free? Yes, even for one window. We check the opening and the sill and give you a written price.

See our window replacement service, the Douglassville brick house windows and our window replacement cost guide for Pennsylvania.

Ask us about your window