The Security Building is an 11-story high-rise building located at 510 South Spring Street within the Spring Street Financial District in Downtown Los Angeles, California. It has been converted to the residential Lofts at the Security Building. It was the former headquarters office building of Security First National Bank, completed in 1906. The building was the tallest building in the city for four years when completed. Landmark The Security Building is a Los Angeles Historic-Cultural Monument, and is a Historic district contributing property to the Spring Street Financial District, listed on the National Register of Historic Places. See also Spring Street Financial District List of Los Angeles Historic-Cultural Monuments in Downtown Los Angeles National Register of Historic Places listings in Los Angeles, California References External links Lofts at The Security Building — Simpson Property Group. Buildings and structures in Downtown Los Angeles Residential skyscrapers in Los Angeles Los Angeles Historic-Cultural Monuments Historic district contributing properties in California National Register of Historic Places in Los Angeles Bank buildings on the National Register of Historic Places in California 1906 establishments in California Office buildings completed in 1906 Chicago school architecture in California