In 2025, 28 US girls were named Kathlyn, making it the 4,818th most common girls’ name of the year, down 2,083 places from #2,735 in 2024. That is 35 fewer than the 63 girls named Kathlyn in 2024. Its best rank for girls was #559, reached in 1914. The most girls given the name in a single year was 125, in 1951. For comparison, it was #5,933 in 2015 and #878 in 1950.
Social Security card records list Kathlyn in 127 years of the 146 from 1880 to 2025, starting in 1897 with 5 babies. In all, 5,156 US babies have been given the name, all of them girls. Its busiest decade was the 1950s, with 851 babies named Kathlyn.
Over the 10 years from 2016 to 2025, 174 US girls were named Kathlyn; the busiest of those years was 2024, with 63. In 2025 that was about 1 in 57,402 of the girls in SSA’s list for the year.
Related spellings in the SSA files include Kathleen (715,336 babies since 1880), Kaitlyn (166,921 babies since 1880), Katlyn (18,438 babies since 1880) and Katlin (5,461 babies since 1880).