The head of the lowland copperhead is small and not obviously distinct from the body. They normally grow to a length of around a metre but on some Bass Strait islands lengths of 1.7 metres have been recorded. The body colour is quite variable, ranging from black through brown to a dull brick red. The sides are usually paler than the back. The most distinctive feature is the white barring over a dark background on the lips. This snake is highly venomous.
This species is adapted to living in a cold temperate climate. They are particularly common around wetlands but also occur in woodlands, grasslands and heath country.
The copperhead feed mostly on frogs and lizards but, occasionally small mammals and birds may be taken.
As an adaptation to living in cold climates, copperheads produce their young alive rather than laying eggs. The 15-30 minute replicas of the adults are totally independent at birth and are fully equipped with venom, which is toxic enough to be considered dangerous to humans.