Lou
Girl name · #2646 in 2025 · Very rare
How old is the name Lou? In official American birth records, Lou has been tracked continuously since 1880, giving it 145 years of documented American history.
In 2025, 65 baby girls were named Lou, placing it at #2646 in the official national rankings. A decade ago it stood at #4725, so the name has been rising over the past ten years. Roughly one in every 27,692 girls born in 2025 was named Lou.
The 145-year story
Lou first appears in the Social Security records in 1880, when 131 girls received the name. Its peak came in 1954, when 1,495 girls were named Lou — good for #204 that year. Today's parents encounter it as a name from their grandparents’ generation, which is precisely the vintage window from which names get revived. Following the curve matters more than today's snapshot: a name's position on its rise-peak-decline arc is the best predictor of how common it will feel in a kindergarten class five years from now.
Babies named Lou per year. Source: Official national birth records.
Unlock the 5-year forecast and compare Lou against up to 5 other names.
Uniqueness: will there be another Lou in class?
On our rarity read — which blends how common Lou is today with its five-year momentum — the name reads as "very rare". A high score means genuine rarity — your Lou will likely be the only one in the room, with the occasional spelling-out as the price.
Where Lou is most common
State-level data for Lou is too sparse in 2025 to rank by rate — in most states its count falls below the SSA's per-state reporting threshold (counts under 5 are withheld).
Names like Lou
Statistically, parents drawn to Lou tend to be choosing among names with similar popularity arcs, era profiles, and sounds — the closest matches in our model are Lynn, Lorna, Lora, Mona, and Marylou.
LynnLornaLoraMonaMarylouDianeLaurieLori
Rank history (last 25 years)
| Year | Babies named Lou | Rank |
|---|---|---|
| 2025 | 65 | #2645 |
| 2024 | 71 | #2508 |
| 2023 | 69 | #2555 |
| 2022 | 62 | #2756 |
| 2021 | 54 | #3037 |
| 2020 | 43 | #3498 |
| 2019 | 40 | #3718 |
| 2018 | 39 | #3789 |
| 2017 | 30 | #4576 |
| 2016 | 35 | #4157 |
| 2015 | 29 | #4725 |
| 2014 | 22 | #5797 |
| 2013 | 15 | #7748 |
| 2012 | 18 | #6872 |
| 2011 | 16 | #7436 |
| 2010 | 11 | #9790 |
| 2009 | 5 | #17294 |
| 2008 | 6 | #15405 |
| 2007 | 6 | #15491 |
| 2006 | 9 | #11417 |
| 2005 | 14 | #7891 |
| 2004 | 10 | #9892 |
| 2003 | 10 | #9671 |
| 2002 | 8 | #11108 |
| 2001 | 8 | #11020 |
Frequently asked questions
How old is the name Lou?
In official American birth records, the name Lou first appeared in 1880 (over 145 years ago), when 131 newborn girls received the name. It has over a century of continuous American history.
Is Lou a popular girl name?
Lou ranked #2646 among girls in 2025 with 65 babies given the name — outside the top 500, making it an uncommon pick. Ten years earlier it ranked #4725.
When was the name Lou most popular?
Lou peaked in 1954, when 1,495 American girls received the name (ranked #204 that year). Since 1954 the name has declined from that high.
How rare is the name Lou?
In 2025, roughly 1 in 27,692 newborn American girls was named Lou. On our rarity scale (rarity blended with momentum) we classify it as "very rare".
Data source: Official American birth records, 1880–2025, national and state files. Counts reflect registered birth records for American families.