- La Jolla
- La Pointe
- Labate
- Labaugh
- Labelle
- Laborde
- Lachina
- Lade
- Laera
- Lafeir
- Lafond
- Lafrance
- Lagrenade
- Lake
- Lakis
- Laliberte
- Lalonde
- Lamb
- Lambert
- Lambertus
- Lambros
- Lamey
- Lampert
- Lancey
- Land
- Landers
- Landry
- Lane
- Langsenkamp
- Lansdale
- Laraway
- Lariviere
- Larkin
- Larocca
- Larosa
- Larsen
- Larson
- Larue
- Lashua
- Latella
- Laterra
- Latman
- Latrobe
- Latz
- Lau
- Laubach
- Laureano
- Lauth
- Laveck
- Law
- Lawrence
- Lawson
- Lay
- Leahy
- Lean
- Leavitt
- Lebida
- Lecher
- Leclair
- Lee
- Leech
- Leete
- Legette
- Lehmann
- Lehrer
- Leide
- Leinicke
- Lekowski
- Lem
- Lemay
- Lemoine
- Lenihan
- Lenz
- Lenzen
- Leon
- Leonard
- Lepelley
- Lerner
- Leslie
- Lesof
- Lesser
- Lethbridge
- Levien
- Levin
- Levine
- Levy
- Lewandowski
- Lewis
- Liang
- Licht
- Lifshutz
- Liggett
- Lilley
- Lilly
- Lilman
- Limehouse
- Lindemann
- Lindgren
- Lindsay
- Linet
- Linhart
- Lipell
- Lipnick
- Lipscomb
- Lisanti
- Littman
- Liu
- Livingston
- Ljosdal
- Llah
- Lloyd
- Lockett
- Loebert
- Loebs
- Lofgren
- Logan
- Loiacono
- Lombardo
- Longo
- Loomis
- Lopez
- Lordan
- Lorenz
- Lorenzo
- Losier
- Loterstein
- Lott
- Louis
- Lovatt
- Love
- Loveday
- Lovett
- Loving
- Low
- Lowe
- Lowenstein
- Lowery
- Lowry
- Lubin
- Lubold
- Lucas
- Ludy
- Luedtke
- Luken
- Lunsford
- Luzinski
- Luzzo
- Lynar
- Lynch
- Lyons