CARLTON is set to lock away a piece of its future with Charlie Curnow on the verge of signing a new two-year contract with the club.

AFL.com.au understands the impressive second-year player, who was due to fall out of contract at the end of this season, has committed to extending his stay at the club until at least the end of 2019.

Curnow, the younger brother of Carlton midfielder Ed, has had a promising campaign so far in 2017 after six games in his debut season last year.

The 20-year-old kicked two goals from 17 disposals in last week's loss to North Melbourne, and has shown his athleticism and power as a forward who can push through the midfield.

He shaped as a priority re-signing for the Blues this season given his status as a first-round pick at the 2015 NAB AFL Draft.

Harry McKay, who was taken two picks earlier than Curnow at No.10 overall in the same draft two years ago, remains out of contract and is yet to make his senior debut despite some good VFL performances.

More than half of the Blues' list remains unsigned for next year, with the list including Ed Curnow, free agents Matthew Kreuzer and Levi Casboult and former Magpie Dale Thomas.

Youngster Carlton players Blaine Boekhorst, Liam Sumner, Kristian Jaksch and Ciaran Byrne are also out of contract as the club heads into the second half of the season.

Curnow's impending signature means there are few first-round picks from 2015 left who haven't yet signed on ahead of next year.

Brisbane Lions forward Josh Schache will continue to weigh his future, while Essendon's Darcy Parish, GWS players Jacob Hopper, Harrison Himmelberg and Matthew Kennedy, and Richmond youngster Daniel Rioli are among the other top-20 picks who remain unsigned.