Redlining is a discriminatory practice in mortgage lending where certain neighborhoods, often those predominantly inhabited by minority groups, are systematically denied access to mortgages, insurance, or other financial services. Lenders would use literal red lines on maps to designate these areas as high-risk or undesirable, refusing to offer loans or offering them at inflated interest rates.

Redlining is a violation of fair lending laws such as the Fair Housing Act (FHA) and Equal Credit Opportunity Act (ECOA). Both of these federal laws prohibit discrimination based on race, color, national origin, religion, sex, family status, or disability in housing and credit transactions.

This practice has historically contributed to racial segregation and economic inequality in the U.S., as minority groups were systematically excluded from access to homeownership and wealth-building opportunities.