Firefighters have warned that incorrect disposal can not only risk bush and grass fires, but also lead to devastation in the home.

The penalty for ignoring the rules, too, can be severe.

Fire and Rescue NSW's Southern Zone Superintendent Stewart Alexander said it was vital that cigarette smokers acted responsibly.

"It is an ignition source, it is a big risk and can easily ignite fires on the side of the road when tossed out the window," he said.

"We have already seen it recently in Albury where a patch of grass was set alight by the freeway from a cigarette, so it is critically important that you dispose of the butts in non-flammable containers so they can be completely extinguished."

The penalty for a driver caught tossing a lit cigarette out the window of a vehicle in NSW is up to an $11,000 fine and 10 demerit points during a Total Fire Ban, or more than $600 and five demerit points on a regular day. Heavy fines also apply to passengers.

Those who spot a driver committing the offence are urged report the incident via the NSW Rural Fire Service's 'report a cigarette butt tosser' website.

A form on the website asks for details such as the tosser's vehicle make, model and registration, as well as the location of where the incident took place, who threw the butt, the direction of travel and nearest town.

Reports must be made within 14 days of the incident occurring, and road users are reminded to only make the report when they are no longer driving.

But the risk of fire caused by an incorrectly disposed cigarette butt also existed in the home, according to Superintendent Alexander.

"The risk of smoking in bed cannot be overstated. Just do not smoke in bed," he said.

"You can fall asleep, drop it, forget about it, and bedding is extremely flammable, so there is serious risk of death or injury."

Superintendent Stewart said the message was simple in all situations.

"Act responsibly, dispose of butts in a non-flammable container and make sure they are completely extinguished," he said.

"Not only will it mitigate that risk of harm, but it will also reduce the impact on the environment."