In an implementation of a computer-implemented method, a target transaction sent by a billing initiator is received, where the target transaction includes bill information of an e-bill to be issued. In response to the target transaction, check logic is invoked in a smart contract deployed in a blockchain network, and a validity check is performed on the bill information. If the validity check succeeds, allocation logic is invoked in the smart contract, and an e-bill number is allocated to the bill information from available e-bill number segments maintained in a blockchain account corresponding to a biller of the e-bill.