Record retention rules require preserving GST accounts for the statutory period, extended when appeals or investigations exist. Registered persons must retain books of account and other records for a baseline statutory period of seventy two months from the due date for furnishing the annual return for the relevant year. If the person is involved in appeal, revision, other proceedings or under investigation for an offence under Chapter XIX, they must retain records relating to that subject matter for one year after final disposal of those proceedings or investigation, or for the baseline period, whichever is later.