Supplementation of sulfur (S) and folic acid (FA) are known to spare the dietary requirement of methionine (Met) in chicken. An experiment was conducted to determine the effects of feeding graded concentrations of FA (0, 2, 4, 6, 8mg kg-1 ) and two concentrations of S (0 and 2g kg-1 ) in 5 × 2 factorial design. Diet without FA and S was considered as negative control (NC). Another diet with the recommended concentration of Met was considered as the positive control (PC). Each diet was offered ad libitum from day 1 to 42 to 10 pens of 20 male chicks each. Broilers fed the NC diet had lower body weight gain (BWG), high feed conversion ratio, lower ready-to-cook yield, higher lipid peroxidation and reduced concentrations of protein and albumin in serum. BWG improved with FA at day 21 and showed a trend of improvement at day 42. Similarly, BWG improved with S supplementation at day 42. The FA and S interaction indicated a significant reduction in lipid peroxidation with S supplementation at the majority of FA levels. Serum protein fractions increased with increased dietary FA content and increased further with S supplementation. Based on the results, it is concluded that the combination of FA (4mg kg-1 ) and S (2g kg-1 ) improved BWG. Similarly, the feed efficiency with 6mg FA alone or with S was similar to the PC group. The improvement was probably due to the increase in protein accretion and reduction in lipid peroxidation with FA and S supplementation. © 2022 Society of Chemical Industry.