A computer-implemented method comprising: receiving, by a central entity computer and from a redeeming entity (102, 403) associated with a user, a request to convert a physical currency to digital currency, the request comprising a serial number and a denomination of the physical currency; generating, by the central entity computer, the digital currency for the denomination and linked to the serial number, wherein the generating comprises recording the digital currency and the serial number to a record of a blockchain (306, 406, 610, 704), wherein the blockchain is stored by a plurality of distributed nodes and wherein the recording of the digital currency on the blockchain is validated by the plurality of distributed nodes, and thereafter the method comprises: transmitting, by the central entity computer and to the redeeming entity, a notification of the generation of the digital currency; causing, by the central entity computer, removal of the physical currency from circulation in a fiat currency system; and associating, by the central entity computer, the digital currency with a digital wallet of the user using a private key stored to the digital wallet, wherein the associating comprises recording a transfer of the digital currency to the user to a record of the blockchain, such that the digital currency is associated with an account of the user. receiving, by a central entity computer and from a redeeming entity (102, 403) associated with a user, a request to convert a physical currency to digital currency, the request comprising a serial number and a denomination of the physical currency; generating, by the central entity computer, the digital currency for the denomination and linked to the serial number, wherein the generating comprises recording the digital currency and the serial number to a record of a blockchain (306, 406, 610, 704), wherein the blockchain is stored by a plurality of distributed nodes and wherein the recording of the digital currency on the blockchain is validated by the plurality of distributed nodes, and thereafter the method comprises: transmitting, by the central entity computer and to the redeeming entity, a notification of the generation of the digital currency; causing, by the central entity computer, removal of the physical currency from circulation in a fiat currency system; and associating, by the central entity computer, the digital currency with a digital wallet of the user using a private key stored to the digital wallet, wherein the associating comprises recording a transfer of the digital currency to the user to a record of the blockchain, such that the digital currency is associated with an account of the user. transmitting, by the central entity computer and to the redeeming entity, a notification of the generation of the digital currency; causing, by the central entity computer, removal of the physical currency from circulation in a fiat currency system; and associating, by the central entity computer, the digital currency with a digital wallet of the user using a private key stored to the digital wallet, wherein the associating comprises recording a transfer of the digital currency to the user to a record of the blockchain, such that the digital currency is associated with an account of the user.