A system and method for reliable and secure record keeping for Radio Access Network (RAN) capacity sharing amongst a plurality of operators using slicing methods according to 3GPP 5G specifications, wherein slicing is controlled by a RAN controller is disclosed. The record keeping system is a distributed Blockchain ledger in which a block specifies information pertaining to available, leased or purchased base station slice(s). The ledger is immutable and available to all operators through a distributed database hosted by each participant wherein each base station owner advertises its leased as well as unused base station capacity at a specific time using blocks in the Blockchain. In an embodiment, the RAN controller directly feeds the information needed to form a new block into the ledger whenever the slicing profile of a RAN changes, thereby making the ledger in complete synchronicity with the network.