- Laaksonen
- Labelle
- Labovitz
- Ladd
- Ladebauche
- Ladley
- Ladnier
- Ladue
- Lafferty
- Lafleur
- Lafollett
- Lagrone
- Lail
- Laine
- Lainis
- Laird
- Lakas
- Lake
- Laliberte
- Lall
- Lam
- Lamal
- Lamare
- Lamb
- Lambe
- Lambert
- Lambeth
- Lambla
- Lambrecht
- Lamere
- Lamond
- Lamorie
- Lampkin
- Lampson
- Lancaster
- Landen
- Landgraf
- Landis
- Lands
- Lane
- Laney
- Lang
- Langan
- Lange
- Langevin
- Langford
- Langley
- Langolf
- Langsam
- Langston
- Lanier
- Lankford
- Lanning
- Lanphear
- Lansche
- Lansdowne
- Lapiana
- Lapping
- Lare
- Larowe
- Larsen
- Larsh
- Larson
- Lash
- Lasher
- Lashua
- Lasner
- Lassiter
- Latessa
- Latham
- Lathan
- Lathem
- Latimer
- Latta
- Laudati
- Laue
- Laughlin
- Laughridge
- Laughrun
- Lautzenheiser
- Lavalley
- Lavender
- Lavery
- Lavoie
- Law
- Lawing
- Lawler
- Lawrence
- Lawrimore
- Lawson
- Lay
- Layel
- Layer
- Layland
- Layman
- Laymon
- Layton
- Lazaroski
- Lazzaro
- Le
- Leach
- Leaird
- Leak
- Leake
- Leamy
- Leary
- Leavitt
- Leazer
- Lebard
- Lebet
- Lebonville
- Lechich
- Lechner
- Leclair
- Ledbetter
- Ledford
- Ledgerwood
- Lee
- Leeds
- Leeper
- Lefler
- Leflore
- Legge
- Leggett
- Legrand
- Legrone
- Legros
- Lehner
- Lehrer
- Lehtinen
- Leibowitz
- Leigh
- Leitner
- Lekson
- Lemaster
- Lemckert
- Lemmond
- Lemonds
- Lemons
- Lenhardt
- Lentz
- Lenz
- Leon
- Leonard
- Leonowicz
- Leotta
- Lerner
- Less
- Lester
- Lett
- Levanson
- Levenson
- Leverette
- Levering
- Leverone
- Levin
- Levine
- Leviner
- Levinson
- Levy
- Lew
- Lewis
- Lhommedieu
- Li
- Liao
- Liberman
- Librizzi
- Liddle
- Lide
- Lidz
- Lieberman
- Lieske
- Liggett
- Lightsey
- Ligon
- Liles
- Lilley
- Lillie
- Lilly
- Lind
- Lindberg
- Lindemuth
- Linder
- Lindland
- Lindler
- Lindquist
- Lindsay
- Lindsey
- Lineberger
- Lineberry
- Liner
- Lingerfelt
- Lingle
- Linick
- Link
- Linkner
- Linnane
- Linson
- Lipack
- Lipe
- Lippard
- Lippert
- Lipscomb
- Lironis
- Lisec
- Lisenby
- Lisk
- Lisman
- Litaker
- Little
- Littlejohn
- Littrell
- Livas
- Livengood
- Livermon
- Livert
- Livingston
- Livoti
- Llewellyn
- Lloyd
- Loberg
- Loch
- Lochary
- Locke
- Locket
- Lockett
- Lockhart
- Locklear
- Lockler
- Lockwood
- Lodewyk
- Loehr
- Lofgren
- Loftin
- Loftus
- Logan
- Lohri
- Loi
- Loman
- Lomax
- Lombardozzi
- Lomeadu
- Loney
- Long
- Longo
- Looker
- Loop
- Lopata
- Loper
- Lopez
- Lore
- Lorie
- Loucks
- Loudermilch
- Louer
- Loughlin
- Louis
- Lovan
- Love
- Lovett
- Lovinggood
- Lovschal
- Lowder
- Lowe
- Lowell
- Lowery
- Lowrance
- Lowry
- Luby
- Lucak
- Lucas
- Lucente
- Lucey
- Lucia
- Luck
- Luckey
- Ludes
- Luebkemann
- Lueke
- Luetze
- Luffman
- Luke
- Lumadue
- Lundberg
- Lundy
- Lung
- Lunsford
- Luong
- Lupo
- Luski
- Luster
- Luther
- Lutkus
- Lutrick
- Lutters
- Luttman
- Luttrell
- Lutz
- Luu
- Luxon
- Luxton
- Lvingston
- Lybrand
- Lyden
- Lyerly
- Lyew
- Lyke
- Lyles
- Lyman
- Lynch
- Lynn
- Lyon
- Lytton