WheelbarrowMath

Retaining Wall Cost Calculator

Estimate what a small block retaining wall costs to build yourself or have installed.

ft
in

Include the cap. Buried courses are added for you.

Block size (face)
in
in
%
Prices (typical US prices; edit for your area)

Typically $2–$10 for interlocking block.

/ton

Crushed stone is typically $30–$38 a ton.Crushed stone is typically $33–$42 a tonne.

/sq ft

Typically $10–$25 a sq ft.Typically $108–$269 a m².

Your Results

Calculating …

What a Retaining Wall Costs

HomeGuide’s cost data for block retaining walls:

Cost per sq ft of wall face
Interlocking block, materials only$4–$20
Installation labor$10–$25
Interlocking block, installed$15–$35

Wall face means the part you can see: length × height above ground. Blocks themselves typically run $2–$10 each.

Worked example. The same 20 ft × 24 in garden wall as on the block calculator page, with 4 × 11.5 in blocks and caps, at the calculator’s default prices:

Cost
133 wall blocks at $4$532
21 caps at $4$84
3.5 tons of base and drainage gravel at $34$119
Delivery$100
DIY materials$835
Installation labor, 38.3 sq ft of face at $17.50$671
Professionally installed$1,506

That works out to about $39 per square foot of visible wall, above the typical range, because a short wall spreads the delivery, gravel, and buried course over fewer square feet. Longer walls bring the per-foot price down.

What Drives the Price

  • Height. Taller walls need more courses, more drainage gravel, and (past the block’s rated height) geogrid reinforcement and engineering ($500–$2,000+ per HomeGuide).
  • Block type. Basic garden blocks cost a few dollars each; large-format and natural-stone-look blocks cost much more but go up faster.
  • Site. Digging in rocky or clay soil, hauling spoil away, and tight access all add labor.
  • Permits. They typically cost $50–$450 where they’re required.

DIY or Hire a Pro?

A low, straight garden wall is a realistic DIY project: the work is digging a level trench, compacting the base, and stacking blocks carefully. A wall that holds back a slope, a driveway, or anything near a building is not: it needs to be engineered. When in doubt, get a quote. A pro can tell you whether your site needs more than a simple gravity wall.

Frequently Asked Questions

How Much Does a Retaining Wall Cost per Square Foot?

HomeGuide puts interlocking block retaining walls at about $15–$35 a sq ft of wall face installed, and retaining walls of all types at $35–$65 a sq ft on average.

How Much Do Retaining Wall Blocks Cost?

Interlocking retaining wall blocks typically cost $2–$10 each, or about $4–$20 per sq ft of wall face in materials.

Do I Need a Permit for a Retaining Wall?

Short garden walls often don’t need one, but rules vary. Permits typically cost $50–$450, and walls over 4 ft usually need an engineered design. Check with your local building department.

Why Does My Small Wall Cost More per Square Foot Than the Averages?

Fixed costs like delivery, base and drainage gravel, and the buried course are spread over fewer square feet, so short or low walls cost more per square foot of visible face.

Sources

Prices are national ballparks checked October 2026. Local prices vary.