The baby name Gillian appears in baby name data for the United States from 1945 to 2023. It was most popular in 1999 with 1,023 babies given the name.
In the later years of this period, Gillian has become more popular compared with earlier years.
| Year | Count |
|---|---|
| 1945 | 5 |
| 1948 | 6 |
| 1953 | 7 |
| 1956 | 6 |
| 1957 | 14 |
| 1959 | 18 |
| 1960 | 10 |
| 1961 | 18 |
| 1962 | 10 |
| 1963 | 20 |
| 1964 | 34 |
| 1965 | 37 |
| 1966 | 36 |
| 1967 | 40 |
| 1968 | 66 |
| 1969 | 74 |
| 1970 | 82 |
| 1971 | 71 |
| 1972 | 63 |
| 1973 | 86 |
| 1974 | 45 |
| 1975 | 54 |
| 1976 | 42 |
| 1977 | 125 |
| 1978 | 138 |
| 1979 | 140 |
| 1980 | 145 |
| 1981 | 161 |
| 1982 | 229 |
| 1983 | 186 |
| 1984 | 184 |
| 1985 | 176 |
| 1986 | 164 |
| 1987 | 209 |
| 1988 | 230 |
| 1989 | 210 |
| 1990 | 195 |
| 1991 | 171 |
| 1992 | 155 |
| 1993 | 137 |
| 1994 | 115 |
| 1995 | 151 |
| 1996 | 344 |
| 1997 | 665 |
| 1998 | 989 |
| 1999 | 1,023 |
| 2000 | 967 |
| 2001 | 860 |
| 2002 | 768 |
| 2003 | 610 |
| 2004 | 606 |
| 2005 | 482 |
| 2006 | 367 |
| 2007 | 372 |
| 2008 | 389 |
| 2009 | 215 |
| 2010 | 174 |
| 2011 | 157 |
| 2012 | 106 |
| 2013 | 50 |
| 2014 | 79 |
| 2015 | 80 |
| 2016 | 78 |
| 2017 | 43 |
| 2018 | 22 |
| 2019 | 11 |
| 2020 | 10 |
| 2023 | 15 |