Illa has been given to about 1,800 people in the United States since 1880. It was most common in 1926, which makes it a interwar name.
Its best year was 1926, when 58 babies were given the name, ranking 983rd. The typical living American called Illa is about 79 years old today.
Source: US Social Security Administration, national and state name files, 2025 release. Etymology researched and written by our editors. Living-population and median-age figures are our own estimates, described in the methodology.