Bay window installation costs $2,500 on average, with most homeowners paying $2,000 to $4,000.1,2 Budget $100 to $150 per square foot for materials and labor, with labor alone running $1,000 to $1,500 per window.1 Prices below are national averages* for 2026.
*National averages, not local quotes. Your price depends on window size, frame material, glass, structural work and local installer rates.
$2,500
average (Angi/Forbes)
$2,000–$4,000
typical range (Angi)
$1,215–$1,851
per window (Homewyse)
$1,000–$1,500
labor per window (Angi)
What sources say
| Source | Figure | Notes |
|---|---|---|
| Angi | $2,500 average, $2,000 – $4,000 | $1,000 – $8,000 extremes; size, frame and glass tables below |
| Forbes | $2,500 average per window, $950 – $7,500 | Replacement $2,250 – $2,500 installed |
| Homewyse | $1,215 – $1,851 per window | Independent estimate, May 2026 |
Angi and Forbes agree on a $2,500 average. The Homewyse independent estimate sits lower at $1,215 to $1,851 per window.1,2,3
Cost by size (Angi)
| Size (ft) | Average cost |
|---|---|
| 4-by-3 | $1,400 |
| 5-by-4 | $2,500 |
| 6-by-4 | $3,000 |
| 5-by-5 | $3,200 |
| 5-by-6 | $4,500 |
| 6-by-6 | $5,400 |
| 6-by-8 | $7,500 |
Cost by frame material (Angi)
| Frame | Average cost |
|---|---|
| Aluminum | $2,000 |
| Vinyl | $2,500 |
| Wood | $2,800 |
| Composite | $2,800 |
| Fiberglass | $3,200 |
Forbes prices frame materials for the window unit alone: aluminum at $375 to $1,800 up to wood at $850 to $3,800.2
Cost by glass type (Angi)
| Glass | Average cost |
|---|---|
| Single-pane | $2,000 |
| Double-pane | $2,500 |
| Triple-pane | $3,300 |
Labor and structural work (Angi)
| Item | Cost |
|---|---|
| Labor per window | $1,000 – $1,500 (40–60% of total) |
| Structural engineer | $550 average |
| General contractor | $250 – $500 average |
| Enlarging an existing opening | $3,000 average |
A bay window projects past the wall, so new openings often need a structural engineer sign-off; replacing an existing bay window avoids most of that. Installing several bay windows at once drops the per-window price from $2,500 to about $2,400.1
DIY or hire
Bay windows are heavy, structural and weather-exposed, so this is pro work. The Home Depot bay and bow windows category shows current unit pricing, which is useful for checking the material share of a quote.
Related guides
Garden Window Cost
Double-Pane Window Cost
Window Replacement Cost
Egress Window Cost
Patio Door Installation Cost
All cost guides
Sources
1. Angi — Bay Window Cost
2. Forbes — Bay Window Installation Cost
3. Homewyse — Cost to Install a Bay Window