9BabyNames Baby names with meanings & US popularity data

Sullivan vs Liam

How Sullivan and Liam compare across 146 years of US Social Security Administration baby-name records — popularity history, peak years, current rank, and which name overtook which.

Open Name Tournament

Sullivan

Male · Irish

Meaning: Dark Eyes. Surname.

Liam

Male · Gaelic

Meaning: Helmeted

US Popularity History — Side-by-Side

Annual US births named Sullivan (boys) vs Liam (boys), from US Social Security Administration national records.

Source: US Social Security Administration. Names appearing fewer than 5 times per year are suppressed by SSA.

Quick Stats

Metric Sullivan Liam
Peak year (most US births) 2025 — 1,083 boys 2024 — 22,164 boys
Peak rank #314 #1
Most recent rank (2025) #314 (1,083 births) #1 (20,818 births)
Total US births since 1880 13,912 343,615
Last 10 years (2016–2025) 8,738 202,429

Peak comparison takeaway

At its all-time peak, Liam reached 22,164 US births in 2024 — 21,081 more than Sullivan's peak count.

Strongest States — Last 10 Years

States where each name ranked highest, from SSA's state-level dataset. Lower average rank = name appears closer to the top of that state's boys-name list.

Sullivan — top 5 states

#StateAvg rankBirths
1 Vermont #92 30
2 Minnesota #131 486
3 South Carolina #144 358
4 Maine #156 88
5 Wisconsin #175 346

Liam — top 5 states

#StateAvg rankBirths
1 Nevada #1 1,758
2 New Jersey #1 6,079
3 Florida #1 14,195
4 Oklahoma #1 1,983
5 New York #1 12,930

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Data & methodology

Source: US Social Security Administration national baby names dataset 1880–2025 (CC0 public domain). Names with fewer than 5 occurrences in a given year are suppressed by SSA. State-level coverage runs 1910–2025. Crossover detection compares annual birth counts (not ranks) for each year both names appear. Methodology: see full notes. More comparisons →