ConcreteBag

How Many Bags of Concrete for a 4x4 Fence Post?

One 4x4 post in a 8" hole 24" deep needs 2 bags of 60 lb concrete.

2bags

60 lb bags · estimated $11.96 at $5.98/bag

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Estimated cost: ~$11.96 (2 × $5.98/bag, Spring 2026 pricing)

Bag size

Material list

  • 2 × 60 lb concrete mix bags $11.96 @ $5.98/bag (Spring 2026)Home Depot ↗Lowe's ↗
  • Wheelbarrow or mixing tub
  • Mixing hoe or drill paddle
  • Margin trowel or float
concrete⌀ 8 in24 in (D)4×4 post

Multi-bag comparison

Bag sizeBagsPrice/bagTotal
80 lbBest value1$6.98$6.98
60 lb2$5.98$11.96
40 lb2$4.98$9.96

Prices are spring 2026 estimates. Above ~60 bags, price a ready-mix truck too — it is often cheaper.

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2 bags(60 lb)
$11.96
Buy at Home Depot

How this is calculated

We convert your dimensions to cubic feet, add a 10% waste buffer for spillage and an uneven subgrade, then divide by the bag's yield and round up to the next full bag.

FAQ

How many bags of concrete per 4x4 fence post?

One 4x4 fence post set in a 8-inch hole 24 inches deep needs about 2 bags of 60 lb or 1 bags of 80 lb concrete, with waste included.

How much concrete do I need for 5 4x4 fence posts?

About 6 bags of 60 lb concrete for 5 posts. Buy one or two extra bags so you do not run short mid-set.

Can I use fast-setting concrete for a 4x4 fence post?

Yes. Many people pour fast-setting mix straight into the hole and add water. The number of bags is the same as standard mix.