Basement Finishing Cost in Idaho Falls (2026 Pricing Guide)

An unfinished basement is 800–1,500 square feet of paid-for square footage your family isn’t using. Finishing it is one of the highest-leverage projects in any Eastern Idaho home. Here’s what it costs in 2026.

2026 cost ranges

• Basic finish (open layout, no bath): $30–$55/sq ft
• Mid-range with bath and bedroom: $55–$85/sq ft
• Premium with wet bar, theater, full bath: $85–$130/sq ft

For a typical 1,000 sq ft Idaho Falls basement with one bedroom, full bath, and a family room: $60,000–$80,000 in 2026.

Where the money goes

• Framing and drywall: $12K–$18K
• Electrical: $5.5K–$9K
• Plumbing (if adding a bath): $7.5K–$13K
• HVAC mods: $2.5K–$5.5K
• Egress window install: $3.5K–$6.5K per window
• Bathroom finish: $9K–$22K
• Flooring (LVP): $4–$8/sq ft installed
• Permitting: $400–$900

Idaho code requirements people miss

• Egress window in every bedroom. 5.7 sq ft min clear opening, max 44″ sill height.
• Smoke and CO detectors hardwired with battery backup.
• Ceiling height 7’0″ min in living areas.
• GFCI protection in bathrooms and within 6 feet of any wet location.
• Permitting required in Bonneville County for framing, electrical, or plumbing.

Timeline

Permit to substantial completion: 8–12 weeks. Add 3–4 weeks for egress excavation.

The ROI question

Mid-range basement finishes in Idaho Falls typically recoup 70–75% at resale. The bigger win is daily livability.