ChildLine wants to double the number of helpline volunteers to 2,000 over the next five years.
The charity announced the target in the wake of its first strategic review, which is planning to overhaul the helpline in order to improve its effectiveness.
At present, ChildLine is swamped with 4,000 calls every day from children but only 1,800 get through. The charity's trustees are examining proposals to double the volunteer force through a variety of measures including flexible hours and creating new regional bases.
Volunteers currently work from 3.30pm to 9.30pm from 10 bases mainly in city centres. Proposals include changing working times and opening new bases in different locations.
Carole Easton, chief executive at ChildLine, said: "There are still children that don't get through (on the helpline). The volunteers themselves identified a need for flexibility according to their travel and working times."