Eleven year-old Imogen Large and her eight year-old sister Amber are cutting their hair for charity.

This year will mark three years for Imogen with her little sister Amber following in her footsteps for the first time.

The Lithgow Public School students will be chopping 36 centimetres off their hair, to be donated to Hair with Heart.

The organisation helps to make wigs for children who have lost theirs due to medical conditions.

Imogen said she enjoyed being able to help those in need.

"I like benefiting kids who need it, and wigs can be quite expensive for families," she said.

"It feels good to be making a difference."

Being her third time cutting her hair, Imogen said it took roughly three years to grow 36 centimetres of hair and while it was a lengthy process, she enjoyed it.

"To me it's just hair at the end of the day but it can make a big difference to someone who needs it.

"So I'll continue doing this for as long as I possibly can," she said.

Amber said she was excited to follow in her sister's footsteps and looked forward to the hair cut.

"I'm a little bit sick of my long hair so I can't wait to cut it and give it to someone who needs it," she said.

The hair cut will take place at Lithgow Information Neighbourhood Centre (LINC) on November 25.

Lithgow Cr Maree Statham will be chopping Imogen's hair while their mother Donna's work colleague will cut Amber's.

"They'll have the cut done at LINC and we've got two hair dressers so they [the girls] can get it cut at the same time," Mrs Large said.

"I'm really proud of them and happy they're doing it," she said.

Imogen and Amber have a fundraising target of $2000 which helps the charity buy back the wigs after they're made and provide them to children in need.

You can donate through their fundraising page here and keep up to date with the girls through their Long Hair - 2 Big Hearts For Variety's Hair with Heart Facebook page.