Background and Objectives: Haemoglobin values of <125 g/L of haemoglobin in whole blood donors account for 15.5% to 55.8% deferrals which is easily treatable. If properly counselled and treated, Anaemic donors can broaden our shrinking voluntary blood donor base. Material and methods: The prospective interventional study was conducted over 18 months in a tertiary care hospital. Blood donors presenting for whole blood donation but deferred for low haemoglobin (< 125g/L) were included. Whole blood donors showing a picture of iron deficiency based on complete blood counts (CBC) and peripheral blood film (PBF) on the sample collected before the initiation of oral iron supplementation (Day 0) were contacted and requested to visit the blood centre. They were counselled and provided ferrous sulphate tablets (325mg containing 100mg elemental iron) to be taken daily after meals for 60 days. Compliance with the intake of iron supplementation was ensured. After completing oral iron supplementation for 60 days, a repeat sample was collected. Results: A significant increase in the mean haemoglobin (109 ± 15 to 126 ± 15 g/L; p value<0.001) and serum ferritin levels in all the donors taking iron supplements. The change in mean Hb after iron therapy was more pronounced in donors with higher pre-treatment mean Hb values. A significant increase in mean Hb concentration in males compared to females (140 ± 13 vs 123 ± 14 g/L; p <0.001) after iron therapy. Conclusion: Oral iron supplementation showed a positive impact after 60 days. Highlights The first-of-a-kind study was done in a developing country where iron supplementation (325mg ferrous sulphate tablet containing 100mg elemental iron) was prescribed in first-time deferred blood donors and response after treatment was studied. A significant increase in the mean haemoglobin (109 ± 15 to 126 ± 15 g/L; p value<0.001) and serum ferritin levels in all the donors taking iron supplements. The change in mean haemoglobin after iron therapy was more pronounced in donors with higher pre-treatment mean haemoglobin values. A significant increase in mean haemoglobin concentration in males compared to females (140 ± 13 vs 123 ± 14 g/L; p <0.001) after iron therapy.