This paper examines the role of two types of reputation - borrower credit history and productivity - in disequilibrium supply and demand models of loan size dynamics in formal and informal credit markets. Using panel data on Honduran households, full- and partial-information regime switching econometric models yield four principal findings: (1) credit contracts in the formal sector are largely collateral driven and not reputation driven; (2) the informal sector credit contracts are borrower reputation based; (3) the informal sector utilizes positive/negative credit histories in both markets to credibly reward/punish borrowers; and (4) technical efficiency has a positive impact in determining loan size in both sectors on the demand and supply side of the market.