Fonnie is a very rare name used for both girls and boys that was most common in the 1910s and has all but disappeared.
Fonnie is predominantly a girl name. It last appears in U.S. records in 1950. Fonnie was first reported in SSA data in 1908 and peaked in 1918 (11 births).
| Year | U.S. births | U.S. + territories | ♀ Rank | ♂ Rank |
|---|---|---|---|---|
| 1950 | 5 | — | #5,563 | — |
| 1949 | 5 | — | #5,504 | — |
| 1943 | 7 | — | — | #3,052 |
| 1941 | 5 | — | — | #3,682 |
| 1939 | 5 | — | #4,470 | — |
| 1938 | 5 | — | — | #3,708 |
| 1936 | 8 | — | #3,210 | — |
| 1935 | 6 | — | #3,926 | — |
| 1933 | 6 | — | #3,908 | — |
| 1932 | 6 | — | #4,077 | — |
| 1930 | 7 | — | #3,801 | — |
| 1929 | 5 | — | #4,836 | — |
| 1927 | 5 | — | #5,077 | — |
| 1926 | 10 | — | #5,127 | #4,442 |
| 1923 | 7 | — | #4,115 | — |
| 1922 | 13 | — | #4,172 | #4,017 |
| 1921 | 9 | — | #3,507 | — |
| 1920 | 5 | — | #5,256 | — |
| 1919 | 14 | — | #3,302 | #4,399 |
| 1918 | 11 | — | #2,886 | — |
| 1917 | 13 | — | #3,857 | #3,703 |
| 1916 | 7 | — | #3,682 | — |
| 1912 | 6 | — | #2,749 | — |
| 1911 | 8 | — | #1,845 | — |
| 1908 | 8 | — | #1,592 | — |