Ildefonso — boys' name

What the Data Says About Ildefonso

The Social Security Administration has registered 392 babies named Ildefonso between 1917 and 2022, spanning 106 consecutive years of U.S. birth records. As a boy's name, Ildefonso currently falls outside the top 1,000 boys' names for 2022. The name reached its historical peak in 1976, when 16 babies received it in a single year.

Decade-level aggregation shows that Ildefonso performed strongest in the 1980s, accumulating 76 births during that ten-year window. Across the 12 decades of recorded activity, Ildefonso shows a clear decline from its mid-century high. Geographically, the name is most concentrated in Texas, which accounts for 30 births — the largest state-level total in the dataset — followed by California. In total, SSA state-level files list Ildefonso in 2 of the 51 U.S. reporting jurisdictions.

No etymological entry is currently available for Ildefonso in our reference dataset. These figures derive from SSA's annual national and state-level name files, which include any name appearing at least five times in a given year or state-year; names below that threshold are suppressed for privacy and therefore excluded from the totals shown here. The 392 total represents a lower bound — actual usage may be higher in years or states where the count fell below the disclosure floor. This page is provided for informational and research purposes only and does not constitute personal, legal, or naming advice.