we made a financial analysis in order to assess the feasibility to invest in fodder banks as an alternative for supplementing animals in dual purpose systems during the dry season (125 days). models were constructed to compare cutting and carrying of perennial woody fodder banks (veranera) cratylia argentea + sugar cane (saccharum officinarum) and browsing fodder banks of leucaena leucocephala with two supplements: concentrates and chicken manure. the indicators used for the financial evaluation of the systems were net present value (npv) and internal return rate (irr). a sensitivity analysis was carried out with an increase in milk, concentrate and chicken manure and labor prices. we found that perennial fodder banks required in average 71.1 man labor year-1 for their management. financial analysis showed that they are profitable when compared to chicken manure (npv= us$ 362.2; irr=17%) and concentrates (npv: us$ 1953.9; irr=39%). fodder banks with leucaena required 13 man labor year-1 for their management.. they are profitable when compared to chicken manure (npv=us$1594.7; irr=21%) and with concentrates (npv=us$3619.6; irr=35%). the models were sensible to changes in milk production, reduction in price of chicken manure and concentrates and reduction both in the labor price and price of milk. in summary, fodder banks are a good alternative for supplementing animal in the dry season and an important source of employment in the region; nevertheless, the high cost of hired labor could limit their adoption.