Techniques and solutions are described for recording document transactions in a blockchain. Document transactions can include sending or receiving a document, or various workflow steps involving a document. Other steps in a workflow that includes a document can be recorded in the blockchain. Blockchain entries related to a document can include a unique identifier of the document, such as a hash value. When a document is sent between two computing systems, the document can be encrypted using a public encryption key of the receiving computing system. Sending and receiving of documents, and recording of blockchain transactions, can be facilitated by an intermediary service. A service providing recording of blockchain transactions can abstract recording details from applications calling the service. A party having the unencrypted document, or the unique document identifier (such as legitimately retaining or receiving the identifier), can retrieve a transaction history of the document from the blockchain.