Santa Ignacia is a municipality in the landlocked province of Tarlac.
The municipality has a land area of 146.07 square kilometers or 56.40 square miles which constitutes 4.79% of Tarlac’s total area. Its population as determined by the 2020 Census was 51,626. This represented 3.43% of the total population of Tarlac province, or 0.42% of the overall population of the Central Luzon region. Based on these figures, the population density is computed at 353 inhabitants per square kilometer or 915 inhabitants per square mile.