A transaction device system is associated with a transaction device proxy account identifier, which may be stored in a database on the transaction device system and may be associated with a transaction account identifier for use in completing a transaction. The proxy transaction device identifier may include at least a first portion which corresponds to a portion of the transaction device identifier. The first portion of the proxy transaction device identifier may be segmented into proxy fields where a first segment includes a portion of a transaction account data set, and a second segment has encoded therein an account provider desired information. The proxy account identifier segments are undetectable by receiving systems such that the proxy account identifier emulates a merchant recognizable data transfer format. The account provider system uses the first portion of the transaction device identifier to reassemble the transaction device identifier for use in transaction completion.