The number of victims has risen from 560 to 741, with 96% aged between four and 20.
Meanwhile, 276 potential suspects have been identified - a rise of 24 in the past three months.
Some 328 football clubs, spanning all tiers of the game, are involved in the inquiry, called Operation Hydrant.
A hotline was set up to report abuse last year when a number of ex-footballers said they were victims as youngsters.
Police forces across the UK have received an increased number of calls from victims and from people offering information.
The investigation is being co-ordinated by the National Police Chiefs' Council (NPCC), which urged anyone who may have been a victim to report it.
Chief constable Simon Bailey, NPCC lead for child protection, said all allegations and information received is being acted on.
"When allegations are reported it enables police to assess whether there are current safeguarding risks and ensure that appropriate action is being taken to prevent children being abused today," he added.
The NPCC said 27 referrals to the inquiry related to sports other than football.
These referrals include basketball, rugby, gymnastics, martial arts, tennis, wrestling, golf, sailing, athletics, cricket and swimming.
The Football Association has also begun an independent review, led by Clive Sheldon QC, into its handling of abuse allegations in the years prior to 2005.
The hotline set up by the NSPCC is available 24 hours a day on 0800 0232642.
Police have identified 181 new victims in the investigation into child sex abuse within football in the UK since April.