As fertility falls below replacement level in several states, India faces a new demographic challenge: fewer workers, faster ageing and a growing economic cost of family formation. India’s fertility rate has fallen to around replacement level nationally, but that headline conceals a far more consequential regional divide. Tamil Nadu’s total fertility rate is 1.7, Maharashtra’s 1.8, while Sikkim remains at 1.1 in NFHS-5. India’s fertility transition is no longer a single natio