The baby name Ildefonso appears in baby name data for the United States from 1940 to 1992. It was most popular in 1968 with 10 babies given the name.
Over the period shown, Ildefonso has stayed at a similar level of popularity.
| Year | Count |
|---|---|
| 1940 | 5 |
| 1946 | 8 |
| 1968 | 10 |
| 1983 | 7 |
| 1992 | 5 |