CostGuideHQ

Basement Excavation Cost: $40,000–$150,000 (Average $105,000) in 2026

Author: CostGuideHQ Editorial·✓ Fact-checked·Updated July 2026·6 min read·4 sources·US national averages, USD
Quick answerQuick answer: Digging out a basement typically costs $40,000 to $150,000, averaging around $105,000 nationally. A basic dig-out runs $30 to $75 per square foot, while a full crawl-space-to-basement conversion runs $50 to $150 per square foot. Home size, soil volume, and whether the house needs raising drive the final price.
  • A basement dig-out typically costs $40,000 to $150,000, averaging about $105,000 nationally (Bob Vila, This Old House, HomeAdvisor).
  • Basic excavation runs $30 to $75 per square foot, while a full crawl-space-to-basement conversion runs $50 to $150 per square foot (Bob Vila, HomeAdvisor).
  • Digging alone costs $75 to $150 per cubic yard of dirt — about $22,500 to $45,000 for a 1,000-square-foot basement (Bob Vila, This Old House).
  • Raising or bracing the house during excavation adds $3,045 to $9,400, and a new foundation adds another $10,000 to $30,000 (Bob Vila, This Old House).

How much does basement excavation cost?

National average
$105,000
total project
Typical range
$40,000–$150,000
Most projects
Whole project
$83,000–$128,000
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Cost by material / type

TypeLowHigh
basement dig-out, per sq ft$30$75
crawl space to full basement conversion, per sq ft$50$150
full basement remodel incl. finishing, per sq ft$30$90
Estimate your cost
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Rough estimate only — get local quotes for exact pricing.

What affects the cost?

  • Project scope — a basic dig-out runs $30-$75 per square foot (Bob Vila) while a full crawl-space-to-basement conversion runs $50-$150 per square foot (HomeAdvisor); blending these two very different scopes is the biggest reason quoted totals vary so much.
  • Dirt volume removed — excavation itself costs $75-$150 per cubic yard; a 1,000-square-foot footprint (about 300 cubic yards) runs $22,500-$45,000 just to dig out (Bob Vila, This Old House).
  • House raising or bracing — temporarily supporting the existing structure during excavation costs $3,045-$9,379 (Bob Vila) or $3,100-$9,400 (This Old House), with full underpinning running up to $20,000 (This Old House).
  • New foundation work — footings, walls, and slab poured after excavation add $10,000-$30,000 (Bob Vila, This Old House).
  • Drainage and plumbing — drainage systems cost $2,000-$5,500 (Bob Vila) to $2,000-$6,000 (This Old House), and plumbing rough-in adds $1,000-$3,000 (both sources).
  • Waterproofing — sealing the new basement against groundwater intrusion adds $2,300-$7,600 (Bob Vila).
  • Permits and engineering — permits run $1,200-$2,000 (Bob Vila, This Old House), and a structural engineer's review adds $2,000-$5,000 on conversion projects (HomeAdvisor).
  • Basement size — cost scales directly with square footage; Bob Vila's size breakdown runs from $15,000 for a 500-square-foot basement to $225,000 for 3,000 square feet.

Why does basement excavation cost so much?

Because you’re moving hundreds of tons of dirt out from under an occupied house, then rebuilding what was underneath it. A typical dig-out project runs $40,000 to $150,000, averaging around $105,000 nationally (HomeAdvisor), and Bob Vila and This Old House both land on the same $60,000 to $150,000 typical range for a full basement dig-out. The digging itself is priced by volume — $75 to $150 per cubic yard of dirt — so a 1,000-square-foot basement, which needs roughly 300 cubic yards removed, costs $22,500 to $45,000 just to excavate (Bob Vila, This Old House). That’s before the house gets raised or braced, a new foundation gets poured, and drainage, plumbing, and waterproofing go in. Each of those steps is its own line item, which is why a basement excavation quote rarely looks like a single number — it’s a stack of separately priced trades.

What’s the difference between a basic dig-out and a full conversion?

It’s the biggest reason quotes vary. A basic dig-out — mostly the excavation labor itself — runs $30 to $75 per square foot (Bob Vila). Converting a crawl space into a genuine full basement, which bundles in raising the house, a new foundation, and structural work, runs $50 to $150 per square foot (HomeAdvisor). Fixr’s basement-remodeling numbers land lower still, $40,000 to $120,000 for a partial-to-full conversion, because that figure is scoped to remodeling work and doesn’t break out excavation as its own cost. None of these numbers are wrong — they’re pricing different scopes of work. Before comparing quotes, ask exactly what’s included: dirt removal only, or removal plus house support, foundation, and rough-ins. New-construction basement digging, where there’s no existing house to raise or underpin, is far cheaper at $10,000 to $30,000 (Bob Vila).

What drives the price beyond the digging itself?

Once the dirt is out, several fixed-cost steps stack on top. Raising or bracing the house during excavation costs $3,045 to $9,379 (Bob Vila) or $3,100 to $9,400 (This Old House), and full underpinning of the foundation can run up to $20,000 (This Old House). A new foundation — footings, walls, and slab — adds $10,000 to $30,000. Drainage systems run $2,000 to $5,500 (Bob Vila) to $2,000 to $6,000 (This Old House), plumbing rough-in adds $1,000 to $3,000, and waterproofing the finished space adds $2,300 to $7,600 (Bob Vila). Permits run $1,200 to $2,000, and conversion projects often call for a structural engineer’s review at $2,000 to $5,000 (HomeAdvisor). Basement size matters too — Bob Vila’s size breakdown runs from $15,000 for a 500-square-foot basement up to $225,000 for 3,000 square feet.

How can I lower my basement excavation cost?

Get clear on scope before you get quotes — a basic dig-out at $30 to $75 per square foot (Bob Vila) is a very different job than a full conversion at $50 to $150 per square foot (HomeAdvisor), and contractors will price accordingly. If your goal is more storage or mechanical space rather than a finished living area, skip the finishing work; Fixr’s basement-remodeling figure of $30 to $90 per square foot only applies once you add flooring, walls, and fixtures on top of the excavation. If you’re building new, dig the basement during initial construction rather than retrofitting one later — new-construction excavation runs $10,000 to $30,000 versus $60,000 to $150,000+ to dig under an existing home (Bob Vila). And get at least two or three itemized quotes so you can see exactly what’s charged for dirt removal, house support, foundation, and drainage separately, rather than one bundled number.

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Frequently asked questions

How much does it cost to dig out a basement?
Most homeowners pay $40,000 to $150,000 to dig out a basement, averaging around $105,000 (HomeAdvisor). Bob Vila and This Old House both put the typical range at $60,000 to $150,000.
How much is basement excavation per square foot?
A basic dig-out runs $30 to $75 per square foot (Bob Vila), while converting a crawl space into a full finished basement runs $50 to $150 per square foot (HomeAdvisor).
What does it cost just to remove the dirt?
Excavation labor alone costs $75 to $150 per cubic yard. For a 1,000-square-foot basement — roughly 300 cubic yards — that's $22,500 to $45,000 (Bob Vila, This Old House).
Do I need to raise my house to excavate a basement?
Often yes, if you're digging under an existing home. Raising or bracing the structure during excavation costs $3,045 to $9,400 (Bob Vila, This Old House), and full underpinning can run up to $20,000 (This Old House).
Is new-construction basement excavation cheaper?
Yes. Digging a basement as part of new construction costs $10,000 to $30,000, far less than digging under an existing home, because there's no structure to raise or underpin (Bob Vila).
What else does a basement excavation project usually include?
Beyond digging, most projects add a new foundation ($10,000 to $30,000), drainage ($2,000 to $6,000), plumbing rough-in ($1,000 to $3,000), waterproofing ($2,300 to $7,600), and permits ($1,200 to $2,000) (Bob Vila, This Old House).
Why do cost estimates for basement excavation vary so much?
Sources scope the job differently. Bob Vila and This Old House price a full dig-out-and-rebuild ($60,000 to $150,000), HomeAdvisor prices a crawl-space conversion ($83,000 to $128,000 typical), and Fixr's basement-remodeling figures ($40,000 to $120,000) reflect a lower-scoped conversion that doesn't itemize excavation separately.

Sources

Figures synthesized and cross-checked across these sources (retrieved 2026-07-28):

  • Bob Vila — Cost to dig out a basement runs $60,000 to $150,000 on average, or $30 to $75 per square foot. By size: 500 sq ft $15,000-$37,500; 1,000 sq ft $30,000-$75,000; 1,500 sq ft $45,000-$112,500; 2,000 sq ft $60,000-$150,000; 2,500 sq ft $75,000-$187,500; 3,000 sq ft $90,000-$225,000. Excavation itself: $75-$150 per cubic yard of dirt (about 300 cubic yards for 1,000 sq ft = $22,500-$45,000). Permits $1,200-$2,000; house bracing about $20,000; house raising $3,045-$9,379; plumbing $1,000-$3,000; drainage $2,000-$5,500; waterproofing $2,300-$7,600; new foundation $10,000-$30,000. By project type: basement deepening $40,000-$90,000; crawl space conversion $50,000-$200,000; new construction $10,000-$30,000; partial-to-full expansion $20,000-$80,000.
  • This Old House — Digging out a basement costs between $50,000 and $150,000 or more, typically $60,000-$150,000 depending on scope and structural complexity; crawl space conversion projects run $47,500-$135,000. Excavation labor: $75-$150 per cubic yard, or $22,500-$45,000 to dig a 1,000-square-foot basement (about 300 cubic yards). Raising the home on jacks: $3,100-$9,400. Underpinning (reinforcing the foundation): up to $20,000. Plumbing $1,000-$3,000; drainage systems $2,000-$6,000; new foundation (footings, walls, slab) $10,000-$30,000; permits $1,200-$2,000. Related: basement finishing $7-$23 per square foot; walkout door installation $2,500-$10,000; foundation repairs $2,100-$7,800.
  • HomeAdvisor — Converting a crawl space to a basement averages $105,000, normal range $83,000-$128,000, or $50 to $150 per square foot. Dig-out cost alone ranges $15,000-$40,000. By size (total conversion): 500 sq ft $25,000-$75,000; 800 sq ft $40,000-$120,000; 1,200 sq ft $60,000-$180,000. Structural engineer $2,000-$5,000; general contractor markup 10%-20% of total project cost; drainage and plumbing installation $3,000-$9,000.
  • Fixr — Converting a partial basement to a full basement averages $40,000-$120,000, the same range cited for expanding or extending a basement. Lowering a basement floor (jackhammering, excavating beneath, pouring a new floor) or benching a basement both run $31,500-$63,000. Converting to a walkout basement costs around $60,000 or more depending on excavation and landscaping needs. Overall basement remodeling runs $30-$90 per square foot, though excavation-specific rates aren't separately itemized.

Sources disagree mainly because they scope the job differently, not because the underlying math conflicts. Bob Vila and This Old House both frame their headline number around 'digging out a basement' and land in the same place: $60,000-$150,000 (Bob Vila) and a typical $60,000-$150,000, up to '$150,000 or more' (This Old House) — both citing the same excavation-labor math of $75-$150 per cubic yard and $22,500-$45,000 to dig a 1,000-square-foot footprint. HomeAdvisor, scoped specifically to full crawl-space-to-basement conversions, reports a tighter and lower typical range: average $105,000, normal range $83,000-$128,000. That average sits almost exactly at the midpoint of the Bob Vila/This Old House range, so we use it as national_average_usd, with HomeAdvisor's normal range as project_low_usd/project_high_usd (the typical-project figure). Fixr's basement-remodeling page reports a lower range ($40,000-$120,000 for a partial-to-full conversion) because it's scoped to remodeling rather than a full dig-out-and-rebuild, and by its own account doesn't break out excavation-specific rates separately. range_low_usd (40,000) and range_high_usd (150,000) widen the published range to capture Fixr's lower-scoped conversion floor on one end and Bob Vila/This Old House's higher dig-out ceiling on the other. The three by_type rows are NOT interchangeable — each reflects a different project scope (basic dig-out vs. full conversion vs. conversion-plus-finishing) as reported by its source. All figures assume digging out under an existing home (crawl space or slab foundation); new-construction basement excavation is typically far cheaper, around $10,000-$30,000, because it doesn't require raising or underpinning an existing structure (Bob Vila).