- Lewis (continued)
- Leycester
- Leyrer
- Leyshon
- Leyson
- Libby
- Libolt
- Librizzi
- Lidyard
- Lie-Nielsen
- Liebensperger
- Liebermann
- Liesenberg
- Liester
- Light
- Lilley
- Lillibridge
- Lillie
- Lilly
- Lily
- Limes
- Limone
- Linaweaver
- Lincoln
- Lindahl
- Lindall
- Lindebak
- Linden
- Lindley
- Lindmark
- Lindquist
- Lindsay
- Lindsey
- Lindsley
- Lindstrom
- Lineburg
- Linehan
- Linen
- Lines
- Linford
- Lingebaugh
- Lingham
- Lingo
- Link
- Linkletter
- Linley
- Linn
- Linnell
- Linscott
- Linsley
- Linton
- Lipe
- Lippincot
- Lippincott
- Lipsett
- Lisbon
- Lisenbee
- Lissenden
- Lister
- Litchfield
- Lite
- Little
- Littlefield
- Littlejohn
- Littlewood
- Littrell
- Livermore
- Livingston
- Lizotte
- Llewellyn
- Lloyd
- Llwyd
- Lobdell
- Locke
- Lockrey
- Lockwood
- Loeber
- Loffler
- Logan
- Logemann
- Logwood
- Lohrentz
- Loiselle
- Lombard
- Lombe
- London
- Londraville
- Londrie
- Lone
- Long