Indian Railways Finance Corporation has extended its Rs 8,600-crore tax-free bond offering, after failing to garner adequate subscription. According to the earlier schedule, the issue was to close on Monday. Now, it has been extended till February 7. IRFC has raised about Rs 2,300 crore, against the total issue size of Rs 8,660 crore, including an option to subscribe bonds worth an additional Rs 7,163 crore. The initial subscription was for Rs 1,500 crore. Meanwhile, National Highways Authority of India’s tax-free bond issue, opened more than a week after the IRFC one, has been fully subscribed, according to provisional figures, primarily due to a relatively attractive coupon rate. The coupon rate offered by NHAI is 8.27 per cent and 8.5 per cent for bonds with tenures of 10 years and 15 years, respectively, while that offered by IRFC is 8.22 per cent and 8.4 per cent for bonds with the same tenures. The coupon rate offered to retail investors — those investing up to Rs 10 lakh — is 25 basis points higher. “Both NHAI and IRFC are not offering the best rates they were allowed to offer. However, the rates offered by NHAI are slightly more attractive and, therefore, the issue has been lapped up first,” said an investment banker.