Onion is highly sensitive to water stress due to the absence of root hairs and shallow root system. Water stress at any growth stage of onion can result in severe loss of yield and profit. Moreover, fresh water availability for irrigation is continuously declining due to population explosion and global warming. There is a dire need to increase water productivity of irrigation systems. Although drip irrigation is highly efficient, its practical application is limited in developing countries due to high installation costs and lack of technical knowledge among farmers. The present research work was conducted in semiarid climate of Faisalabad, Pakistan to examine low cost irrigation methods for their profitability for onion production even under limited water availability. A field study was conducted using two onion cultivars (Dark red and Robina) with and without mulch under three irrigation methods (furrow, fixed furrow and alternate furrow) during two consecutive winter seasons (2012-13 and 2013-14). Results showed that profitability of onion bulbs produced under alternate furrow irrigation method with mulching was at par with bulbs produced by furrow irrigation without mulching (common method used by farmers). Among onion cultivars "Dark red" was found more consistent in generating a profit under limited water supply than "Robina". From the experimental results it may be concluded that under limited supply alternate furrow irrigation can be successfully used as an effective low cost substitute of normal furrow irrigation. The results showed that profitability of alternate furrow may be enhanced by the application of mulching.