how much does it cost to build a underground pool

July 7, 2026

How Much Does It Cost to Build an Underground Pool?

An underground (inground) pool in the U.S. typically costs $25,000–$120,000+ installed, with most standard projects landing around $50,000–$90,000 depending on type, size, and location.

“Underground pool” is just industry speak for an inground pool —the pool shell is built below ground, often with a deck or patio around it.

Quick Cost Summary by Pool Type

Pool Type| Typical Total Cost (Installed)| Key Characteristics
---|---|---
Vinyl liner| $25,000 – $65,000| Cheapest option, smoother feel, liner needs replacement every 7–15 years 3
Fiberglass| $30,000 – $85,000| Pre-made shell, fast install, lower maintenance, limited shapes/sizes 3
Gunite (concrete)| $50,000 – $120,000+| Custom shapes, premium look, very durable, highest labor and long-term maintenance 3

These are national averages; your actual price can be significantly higher or lower based on local conditions.

Why Prices Vary So Much

1. Size and Shape

A basic 12×24 ft rectangular pool is far cheaper than a large, freeform, spa-integrated design.
Each extra foot of length/width increases excavation, materials, and labor, pushing costs upward.

2. Excavation and Site Conditions

Soft soil (sand) is easy and cheap to dig: ~$2.50–$15 per cubic yard.
Rocky soil or bedrock can jump to $50–$200+ per cubic yard.

Sloped yards, tight access, or nearby structures all add complexity and cost.

3. Location (City & State)

The same 15×30 ft pool might start at $50,000 in Phoenix or Tampa but $80,000 in Chicago or Boston due to labor rates, climate, and code requirements.

Coastal or high-demand areas often have higher builder prices.

4. Extras and Upgrades

Common add-ons that can add thousands:

Decking/patio : $5–$50 per sq ft depending on material (concrete vs pavers).

Fencing : $15–$25 per linear foot (often legally required).

Heater : $1,500–$6,000 installed.

Automatic cover : $8,000–$20,000; manual cover $1,000–$3,600.

Underwater lighting : $700–$1,800.

Water features, tanning ledges, cabanas, and landscaping can each add $5,000–$30,000+.

5. Permits and Codes

Permit fees vary by municipality but can be $500–$5,000+.
Some areas require safety barriers, alarms, or specific fencing, which adds to the total.

Estimated Total Cost Breakdown (Example)

For a mid-range 14×28 ft gunite pool in a moderate-cost area:

Item| Estimated Cost
---|---
Excavation & site prep| $8,000–$15,000
Gunite shell & steel| $25,000–$40,000
Plumbing & electrical| $6,000–$10,000
Finish (tile, stone, plaster)| $4,000–$8,000
Equipment (pump, heater, etc.)| $6,000–$12,000
Decking (basic concrete)| $5,000–$12,000
Permits, fencing, misc| $2,000–$6,000
Total| ~$56,000–$103,000

This matches the typical $50,000–$120,000 range for gunite pools.

Long-Term Costs to Consider

Building the pool is only part of the story. Annual costs often include:

Maintenance chemicals & electricity: $1,200–$3,000+ per year.
Major maintenance : resurfacing concrete every 10–15 years ($10,000–$20,000), replacing vinyl liner every 7–15 years ($3,000–$7,000).

Insurance : many insurers raise premiums with an inground pool.

Money-Saving Tips If You’re Planning One

Pick a simpler shape : rectangles are cheaper than freeform.
Limit extras : install decking and lighting now; add a spa or water feature later.
Consider fiberglass or vinyl if budget is tight and you’re okay with fewer custom options.

Get multiple bids : prices vary widely between builders even in the same city.
Check financing : home equity loans or pool-specific loans can help, but interest rates still matter in 2026.

If you tell me your city, desired size, and preferred type (vinyl, fiberglass, or gunite), I can narrow this down to a much tighter estimated range for your specific situation. Information gathered from public forums or data available on the internet and portrayed here.