It is a deepwater species found in subtropical and temperate Australian waters.

[2] Sepia cultrata has a pale buff pinkish brown colour.

The cuttlebone is an elongate oval shape with triangular pointed anterior and narrow posterior ends.

[2] The knifebone cuttlefish typically inhabits waters between 300 and 500 m deep.

The species' known depth range extends from 132 to 803 m.[2] The type specimen was collected in Twofold Bay, New South Wales and was described by William Evans Hoyle in 1885.