- La Rosa
- Labahn
- Labatt
- Labeau
- Labrosse
- Labuda
- Lacam
- Lacasse
- Lachance
- Lachmann
- Lacinski
- Laclair
- Lacomb
- Ladenburg
- Ladin
- Lafarga
- Lafferty
- Lafontaine
- Lafrance
- Lafrese
- Lagen
- Lagerbom
- Lagneaux
- Lagorce
- Lagrange
- Laguna
- Lahargoue
- Lahiff
- Laing
- Lainson
- Laird
- Lake
- Lam
- Laman
- Lamanda
- Lamantia
- Lamar
- Lamarche
- Lamb
- Lamberson
- Lamberston
- Lambert
- Lamer
- Lamfers
- Lamond
- Lamoreaux
- Lamoureux
- Lampert
- Lamprecht
- Lampton
- Lamse
- Lan
- Lancaster
- Land
- Lander
- Landers
- Lane
- Laney
- Lang
- Langan
- Lange
- Langer
- Langford
- Langlais
- Langlois
- Langwig
- Lansdon
- Lansing
- Lansman
- Laplante
- Laprise
- Lardner
- Lareice
- Lark
- Larkin
- Larmey
- Larpenteur
- Larribas
- Larrinaga
- Larsen
- Larson
- Larue
- Lasky
- Lasota
- Lasseter
- Latham
- Latoshkina
- Latozas
- Laturco
- Lau
- Laue
- Lauen
- Lauer
- Laughlin
- Lauher
- Laurents
- Lauria
- Lauro
- Lauver
- Laux
- Lavelle
- Lavoie
- Lavu
- Lawless
- Lawlor
- Lawrence
- Lawrie
- Laws
- Lawson
- Lax
- Layton
- Lazaroff
- Le
- Le Grand
- Leach
- Leafgren
- Leahy
- Leal
- Leaman
- Leane
- Learnan
- Leary
- Leavelle
- Leavitt
- Lebby
- Lechenet
- Leclair
- Lecompte
- Lecroy
- Lederer
- Ledesma
- Ledford
- Ledingham
- Leduc
- Lee
- Leech
- Leedale
- Leek
- Leer
- Leeser
- Leeth
- Lefevre
- Lefko
- Lefkowitz
- Lefton
- Leggett
- Legler
- Legvold
- Lehardy
- Lehman
- Lehmann
- Lehner
- Lehr
- Lei
- Leichty
- Leigh
- Leiken
- Leinbach
- Leisure
- Leko
- Lelicoff
- Lem
- Lemaux
- Lemieux
- Lemoine
- Lemons
- Lemos
- Lenard
- Lenardon
- Lenhart
- Lenharth
- Lenihan
- Lent
- Lents
- Lenz
- Leon
- Leonard
- Leones
- Leonhart
- Leotaud
- Lerman
- Lerner
- Lescarbeau
- Lescavage
- Leschak
- Lesem
- Lesher
- Leska
- Leslie
- Lesnick
- Lesser
- Lessnau
- Lester
- Lestingi
- Leto
- Leusch
- Leuthold
- Levardi
- Leversedge
- Levin
- Levine
- Levitan
- Levkowitz
- Levy
- Lewis
- Lewnes
- Leyva
- Leyvas
- Li
- Lialios
- Liberis
- Liby
- Licea
- Lichtenhan
- Lieber
- Lieberman
- Liebert
- Liebeskind
- Liebig
- Liebl
- Liese
- Liggins
- Light
- Lightfoot
- Likness
- Lilley
- Lillie
- Lim
- Limbaugh
- Limbert
- Limp
- Limperis
- Lincoln
- Lind
- Lindberg
- Linde
- Lindeman
- Linden
- Lindenberger
- Lindenlaub
- Lindflott
- Lindley
- Lindner
- Lindquist
- Lindroth
- Lindsay
- Lindsley
- Lindstrom
- Line
- Linebarier
- Linehan
- Linesch
- Ling
- Lingle
- Link
- Linkhart
- Linneen
- Linsenbach
- Lintz
- Linzy
- Liosatos
- Lioy
- Lipke
- Lipkina
- Lipman
- Lippert
- Lipsman
- Liptak
- Lisalda
- Lisberg
- Liska
- Liske
- Lislegard
- List
- Liston
- Listzwan
- Litalien
- Litle
- Littell
- Litten
- Little
- Littlefield
- Littman
- Littrell
- Liu
- Lively
- Liverman
- Livings
- Livingston
- Lizarraga
- Lizotte
- Llamas
- Llmas
- Lloyd
- Lo
- Loban
- Lobaugh
- Loch
- Lochner
- Lock
- Lockaby
- Lockard
- Locke
- Lockwood
- Loder
- Loeb
- Loeffler
- Loehr
- Loewenheim
- Lofquist
- Loftus
- Lofty
- Logan
- Lohmeier
- Lohn
- Lohner
- Lohr
- Lohse
- Lombardi
- Lomeli
- Lonergan
- Long
- Longaker
- Longanecker
- Longhofer
- Longo
- Longoni
- Longseth
- Longwell
- Loomis
- Lopes
- Lopez
- Lordeman
- Lorenz
- Lorenzen
- Lorenzini
- Loreto
- Loring
- Losey
- Losik
- Losin
- Loss
- Lossau
- Lotis
- Lott
- Lotze
- Louie
- Louis
- Louthain
- Love
- Lovegren
- Lovette
- Lovio
- Lowe
- Lowell
- Lowenstein
- Lowes
- Lowry
- Loyash
- Loyer
- Lubben
- Lucas
- Lucchesi
- Lucero
- Luciani
- Lucio
- Luckett
- Ludlam
- Ludwig
- Luevano
- Lugerner
- Lugo
- Lujan
- Lukanuski
- Lukas
- Luke
- Lukecart
- Luna
- Lund
- Lunda
- Lundgren
- Lundquist
- Lunsford
- Lunt
- Lupo
- Lurvey
- Luscombe
- Lusk
- Lussier
- Luthi
- Lutz
- Luu
- Lybeck
- Lyle
- Lynch
- Lynde
- Lynn
- Lyon
- Lyons