Background Spina bifida and anencephaly are major neural tube defects largely preventable through maternal periconceptional intake of folic acid. We estimated the global proportion of folic acid‐preventable spina bifida and anencephaly (FAP SBA) prevented through mandatory folic acid fortification of cereal grains, including wheat flour, maize flour, and rice, at the end of year 2020, a time point marking the 30th anniversary of the publication of landmark British Medical Research Council (MRC) study providing unequivocal knowledge on folic acid's FAP SBA prevention potential. Methods The Food Fortification Initiative database was used to identify countries with mandatory fortification policies with folic acid added to cereal grains. We examined the status of FAP SBA prevention assuming mandatory folic acid fortification at 200 mcg/day of folic acid protects against FAP SBA and reduces their prevalence to a minimum achievable rate of 0.5 cases/1000 live births. Results Our analysis showed that 61,680 FAP SBA cases were prevented in the year 2020 through mandatory folic acid fortification of cereal grains in 58 countries, translating to 22% prevention of total possible FAP SBA prevention globally. Many countries in Africa, Asia, and Europe are yet to implement fortification. In 2020, 30 years after the MRC study was published, 218,270 preventable FAP SBA cases still occurred globally. Conclusion Global prevention efforts for FAP SBA are inadequate even after three decades of knowledge on their prevention. Universal mandatory fortification of staples should be urgently implemented to prevent thousands of FAP SBA and associated elective terminations, stillbirths, and child mortality.