The sex abuse scandal is one of the biggest crises the FA has ever faced.
Clive Sheldon QC, the leader of the independent review, stated: "Due to the ongoing criminal investigations and prosecutions it has not been possible for all those who want to speak to the review to be able to do so.
"Whilst I had hoped and expected to complete my review this autumn, I believe this extension will ensure many more individuals who want to engage with the review will be able to do so.
"It is essential that the review is as comprehensive as possible."
Barry Bennell was sentenced for 31 years in prison in January for abusing 12 boys, mainly whilst with Crewe Alexander, while Higgins was found guilty by courts in July for indecently assaulting a young traininee, though the prosecution seeked a retrial after the case was dismessed.
A statement from Sheldon, working with 'Operation Hydrant', also said: "He has decided that he should not finalise his review until he has had the opportunity to speak to more individuals associated with the re-trial of Bob Higgins and the further allegations being made against Barry Bennell, and to receive and analyse any other information about abuse in football that may emerge over the coming months.
"If during this extended period, new witnesses wish to come forward, then Mr Sheldon and his team would be pleased to hear from them."