Poverty Line Act of 2023 This bill revises the methodology used to calculate the federal poverty guidelines. The federal poverty guidelines are used to determine eligibility for many federal and state public assistance programs, including the Supplemental Nutrition Assistance Program (SNAP), the Children’s Health Insurance Program (CHIP), and the National School Lunch Program. The poverty guidelines are currently calculated by adjusting the Census Bureau’s poverty thresholds to account for changes in the Consumer Price Index. The bill requires the Department of Health and Human Services (HHS) to calculate regional poverty guidelines based on a combination of factors including average household expenditures on food, clothing, utilities, and transportation; the average cost of rental housing; and the average cost of health insurance. These factors shall be calculated using regional data as applicable. HHS must make available to the public a tool for determining the poverty guideline applicable to a given household. The new regional poverty guidelines established by HHS may not be lower than existing, corresponding poverty guidelines as of the date of enactment of the bill. HHS shall review and evaluate the poverty guidelines at least every four years and propose changes to this methodology as appropriate. The bill shall take effect three years after its enactment.