Objectives: The main objective of this study is to substantiate the effects of spandex on the properties of plain jersey fabric as compared to the commercial knit sports wear. Method: Three single jersey plain knitted fabric samples were produced with full feeder spandex (4.45%), half feeder spandex (2.22%), and without spandex. 34/1 Ne cotton yarn and 20D spandex were used. Standard test methods were followed to analyze the fabric properties. ASTM D 3774: 2004, ISO 6330:2012, ISO 12945-2, ISO 12947-1:1998 and ISO 13938- 1:1999 methods were used to measure the variation between cotton and cotton/spandex plain jersey fabric, different physical properties in particular GSM, width, abrasion resistance, pilling, bursting strength, and shrinkage of the specimens. Findings: The physical, dimensional, and mechanical properties of cotton/spandex plain jersey knitted fabrics were investigated. The results were compared between knitted fabrics made from 100% cotton and spandex with cotton. The effect of spandex percentage was also studied. A significant effect was observed on the physical, dimensional, and mechanical behaviors of single jersey fabric. Results revealed that the GSM, shrinkage, abrasion resistance, and bursting strength increased and the width reduced with the increased amount of spandex percentage. No apparent effect on the pilling resistance was observed. Applications: The manufactured spandex incorporated knitted fabrics can be found in a wide range of applications. The main endeavor is to use for active sportswear. Keywords: Bursting strength; cotton yarn; pilling resistance; spandex; single jersey; sportswear