The sample method is much more economical than a complete census. In a sample enquiry, there is reduction in the cost of collection of the information, administration, transport, training and man hours.
Although, the labour and the expenses of obtaining information per unit are generally large in a sample enquiry than in the census method, the overall expenses of a sample survey are relatively much less, since only a fraction of the population is to be enumerated. This is particularly significant in conducting socio-economic surveys in developing countries with building economics who cannot afford a complete census because of lack of finances.