Sue Slipman has agreed to stay on as Foundation Trust Network chief executive until the organisation finds a new full-time replacement.
The FTN has recently interviewed for a new chief executive but has chosen not make an appointment.
Ms Slipman initially said she would be standing down in April 2012 and intended to take on a “non-executive portfolio career”.
A spokeswoman for the organisation said the network would now re-advertise for the role and Ms Slipman would remain in post until an appointment had been made.
The FTN split from the NHS Confederation in June and the organisation has more than 200 members.
When all trusts become foundations the FTN is expected to represent the interests of the entire NHS provider arm.
Its membership is largely acute trusts but includes mental health, ambulance and aspirant community foundation trusts.