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Bolt Edge Distance: AISC Values and the 2010 Change

Last updated July 28, 2026

This information applies to the American Steel Industry.

This page carries the older AISC minimum edge distance table — the one with two columns, a larger set for sheared edges and a smaller set for rolled or cut edges. That table was superseded in 2010. It is kept here, clearly labelled, because a great many charts still in circulation look like it and because anyone maintaining a project designed to an older Specification still needs to read it.

If you want the current values, or the metric AS 4100 series alongside them, they are on minimum edge distance for bolts.

What changed in 2010

AISC removed the sheared-edge distinction in the 2010 Specification. The reasoning was that the bearing and tearout checks elsewhere in the code do not care how the edge was cut, and those checks had come to govern — so carrying a separate, larger column for sheared edges in the edge distance table no longer bought anything.

What remains in ANSI/AISC 360 today is a single column, and it is the smaller of the two former columns:

Nominal Bolt
Diameter (in.)		Minimum Edge
Distance (in.)
1/23/4
5/87/8
3/41
7/81 1/8
11 1/4
1 1/81 1/2
1 1/41 5/8
Over 1 1/41 1/4 x Dia.

Confirm against the edition your project is designed to before detailing from any chart on a website, including this one.

The superseded table (pre-2010)

Kept for reference. Do not detail new work from this.

Minimum Edge Distance, in. (Center of Standard Holea to Edge of Connected Part)

Nominal Bolt
Diameter (in.) 		At Sheared
Edges 		At Rolled Edges of
Plates, Shapes or Bars
Gas Cut or Saw-cut Edges b
1/2 7/8 3/4
5/8 1 1/8 7/8
3/4 1 1/4 1
7/8 1 1/2c 1 1/8
1 1 3/4c 1 1/4
1 1/8 2 1 1/2
1 1/4 2 1/4 1 5/8
Over 1 1/4 1 3/4 x Dia. 1 1/4 x Dia.

a For oversized or slotted holes, an increment is added — see standard hole and slot sizes.
b All edge distances in this column may be reduced 1/8-in. when the hole is at a point where stress does not exceed 25% of the maximum design strength in the element.
c These may be 1 1/4 in. at the ends of beam connection angles.

Compare the two tables and the pattern is clear: the right-hand column above is what survived, unchanged, row for row. Nothing was made more permissive in 2010 — the larger column was simply dropped as redundant.

What this means in practice

  • An old chart is conservative, not wrong. Detail to the sheared-edge column and nothing will fail a check. You will just be using more steel than you need to.
  • Reviewing is where it bites. Check someone else’s connection against a pre-2010 chart and you will flag edge distances the current code accepts. That is a wasted RFI and an argument you will lose.
  • Watch the two footnotes. Both belong to the old table. The 1/8-in. reduction and the 1-1/4 in. allowance at beam connection angle ends are conditions of a Specification that no longer reads that way.
  • The edge condition still matters elsewhere. AS 4100 has never merged its columns — it still sets the minimum at 1.75, 1.50 or 1.25 times the bolt diameter depending on how the edge was made. A drawing detailed to Australian practice will look different for that reason, not because someone got it wrong.

Anchor bolts are a different problem

Hole sizes for steel-to-steel connections are not hole sizes for steel-to-concrete anchorage. Shop-drilled steel is made under good quality control; anchor rods cast into a foundation are not, which is why base plate holes are deliberately oversized and why plate washers are usually required over them.

That is a longer story than fits here, and it is set out in full — including the AISC oversized base plate hole table and the placement tolerances the ASCC recommends — on standard hole and slot sizes for bolts.

More steel detailing references

References