Cost to Whole-House Dehumidifier Installation in St. Louis, MO (2026)
If you’re budgeting a whole-house dehumidifier installation in St. Louis, most projects run $1,663-$4,109, 2% below the $2,800 national average. What moves that number most is usually one thing: Unit Capacity (Pints per Day). On its own it can swing the cost by $400 - $1,500, so that’s the decision to slow down on before you sweat the smaller stuff.
Easiest place to save: Fix moisture sources first - sealing basement cracks ($200-$500) and improving grading may reduce your humidity enough to downsize the dehumidifier by one capacity tier, saving $400-$800
In the Midwest (where St. Louis sits): Moderate demand, competitive contractor market.
$1,663-$4,109 in St. Louis
2% below the national average · 0.98x cost multiplier
In St. Louis, a whole-house dehumidifier installation runs $1,663 to $4,109 on average - about 2% below what homeowners pay nationwide. The Midwest market's labor costs account for most of the gap, with material pricing and local permitting fees adding to the spread. Use the cost table below to compare budget, mid-range, and premium options side by side.
Cost Breakdown in St. Louis
| Line Item | Low | Mid | High |
|---|---|---|---|
| Materials | $752 | $1,410 | $2,632 |
| Labor | $525 | $945 | $1,575 |
| Permits | $0 | $0 | $94 |
| Total | $1,277-2% vs. national avg | $2,355-2% vs. national avg | $4,489-2% vs. national avg |
Budget
Basic 70-pint whole-house dehumidifier tied into existing ductwork with gravity drain
Mid-Range
90-pint ducted dehumidifier with dedicated return, condensate pump, and humidistat controls
Premium
High-capacity 130+ pint commercial-grade unit with dedicated ductwork, smart controls, and whole-house coverage for 3,000+ sq ft
Material Options
Material prices below are national averages; availability in St. Louis may shift costs slightly.
| Material | Cost/Unit | Best For |
|---|---|---|
| Standard Ducted Dehumidifier (70 pint) | $800-$1,200 | Average-sized homes in moderate humidity areasAffordable, handles most homes, widely available, easy to service |
| High-Capacity Ducted (90-100 pint) | $1,200-$1,800 | Homes 2,500-3,500 sq ft or in high-humidity regions like the Gulf CoastHandles larger homes, better energy efficiency ratings, quieter operation |
| Commercial-Grade (130+ pint) | $2,000-$3,500 | Large homes, finished basements with persistent moisture, or coastal propertiesHandles extreme humidity, covers 3,000+ sq ft, longest warranties |
| Ventilating Dehumidifier | $1,500-$2,500 | Tight new-construction homes that need both dehumidification and fresh air exchangeBrings in fresh outdoor air while dehumidifying, improves IAQ, meets ventilation codes |
Other Projects in St. Louis
St. Louis Estimate
Typical Range
$1,663-$4,109
vs. National Average
2% below national
Cost Multiplier
0.98x
This 0.98x estimate prices St. Louis labor from BLS Occupational Employment and Wage Statistics (May 2025) and applies a lighter regional adjustment to materials and permits, which vary less by metro than labor does. Actual bids vary by contractor, project scope, and timing.
See national average costs →