Faiths including Buddhism, Jehovah's Witnesses and Baptists and religious settings such as mosques and synagogues will all fall within the scope of the newly announced probe.
The investigation into child protection in religious organisations and settings is the inquiry's 14th strand.
The IICSA said more than one in ten survivors of child sexual abuse who shared their accounts with the inquiry's Truth Project reported sexual abuse in a religious institution.
Of these, almost a quarter said they were abused in institutions in the scope of the new investigation.
The IICSA said the latest strand will review the current child protection policies, practices and procedures in religious institutions in England and Wales.
Other organisations falling under the remit of the investigation will include non conformist Christian denominations, Methodists, Islam, Judaism, Sikhism and Hinduism.
A new investigation into child protection in religious organisations & settings will take place in 2020.— InquiryCSA (@InquiryCSA) May 2, 2019
Jehovah's Witnesses, Baptists, Methodists, Islam, Judaism, Sikhism, Hinduism and Buddhism will fall under its remit.
More here: https://t.co/ptdbMB9ZNo#InquiryCSApic.twitter.com/sbKqAJOlkQ
Other religious settings being considered are churches, temples, Muslim madrassas, Christian Sunday schools, and places where children and young people gather in connection with their religious beliefs, including youth groups and camps.
The investigation is separate from the investigations into the Anglican and Roman Catholic churches.
Organisations and individuals are being invited to apply for core participant status.
A preliminary hearing will take place in July and public hearings are expected to begin next year.
The inquiry is being chaired by Professor Alexis Jay OBE (pictured at the top of the article).
Stay up to date with the latest news stories from a Christian perspective. Sign up to our daily newsletter and receive more stories like this straight to your inbox every morning.