Electrical Conduit Hole Saw Sizes

Dear Mr. Electrician: I plan to install a lot of electrical conduit.  I know that I will need to drill holes or use a knockout punch in junction boxes and load centers.  What are the actual drilling sizes for the various trade sizes of electrical conduit?

Answer: I have posted the drill and knockout sizes for electrical conduit below.  For electricians hole saw kits see here.

For 1/2″ conduit, drill using a 7/8″ hole saw or 1/2″ conduit knockout punch.

For 3/4″ conduit, drill using a 1 1/8″ hole saw or 3/4″ conduit knockout punch.

For 1″ conduit, drill using a 1 3/8″ hole saw or 1″ conduit knockout punch.

For 1 1/4″ conduit, drill using a 1 3/4″ hole saw or 1 1/4″ conduit knockout punch.

For 1 1/2″ conduit, drill using a 2″ hole saw or 1 1/2″ conduit knockout punch.

For 2″ conduit, drill using a 2 1/2″ hole saw or 2″ conduit knockout punch.

For 2 1/2″ conduit, drill using a 3″ hole saw or 2 1/2″ conduit knockout punch .

For 3″ conduit, drill using a 3 5/8″ hole saw or 3″ conduit knockout punch.

For 3 1/2″ conduit, drill using a 4 1/8″ hole saw or 3 1/2″ conduit knockout punch.

For 4″ conduit, drill using a 4 1/2″ hole saw or 4″ conduit knockout punch.

For 5″ conduit, use a 5 1/2″ hole saw or 5″ knockout punch.

For 6″ conduit, use a 6 3/8″ hole saw or 6″ conduit knockout punch.

See my post describing various electrical conduit types.

Electrical Conduit Dimensions: 1/2″ (16)

3/4″ (21)        1″(27)       1 1/4″ (35)

1 1/2″ (41)        2″ (53)        3″ (78)

3 1/2″ (91)        4″ (103)      5″ (129)

6″ (155)

See my post describing the various types of electrical conduit.