L
- Laclede
- La Clede
- Lacon
- La Crosse
- Ladd
- La Fayette
- La Fox
- La Grange
- La Grange Park
- La Harpe
- La Hogue
- Lake Barrington
- Lake Bluff
- Lake Catherine
- Lake City
- Lake Corner
- Lake Creek
- Lake Forest
- Lake Fork
- Lake in the Hills
- Lake Ka-ho
- Lakemoor
- Lake of the Woods
- Lake Park Estates
- Lake Summerset
- Lakeview
- Lake Villa
- Lakewood
- Lakewood
- Lakewood
- Lakewood Shores
- Lake Zurich
- Lamb
- LaMoille
- Lamone Village
- Lanark
- Lancaster
- Landes
- Lane
- Lanesville
- Langham
- Langley
- Langleyville
- Lansing
- Lanton
- La Place
- La Prairie
- La Prairie Center
- Larchland
- Larkdale
- La Rose
- La Rue
- La Salle
- Latham
- Latham Park
- Latona
- Laura
- Laurette
- Lawler
- Lawndale
- Lawn Ridge
- Lawrence
- Lawrenceville
- Layfield
- Leaf River
- Leamington
- Leanderville
- Lebanon
- Ledford
- Lee
- Lee Center
- Leeds
- Leesburg
- Leesville
- Lehigh
- Leisure City
- Leland
- Leland Grove
- Lementon
- Lemont
- Lena
- Lenzburg
- Leonard
- Leon Corners
- Leonore
- L'Erable
- Lerna
- Le Roy
- Lester
- Leverett
- Levings
- Lewisburg
- Lewistown
- Lexington
- Liberty
- Liberty Hill
- Libertyville
- Lick
- Lick Creek
- Lightsville
- Lilly
- Lillyville
- Lily Cache
- Lily Lake
- Lilymoor
- Lima
- Lincoln
- Lincoln Estates
- Lincoln Heights
- Lincoln Hills
- Lincolnshire
- Lincolnwood
- Lincolnwood Hills
- Lindenhurst
- Lindenwood
- Lintner
- Lipsey
- Lis
- Lisbon
- Lisbon Center
- Lisle
- Litchfield
- Literberry
- Lithia
- Little America
- Little Indian
- Little Oklahoma
- Little Rock
- Little Rock
- Littleton
- Little York
- Lively Grove
- Liverpool
- Livingston
- Loami
- Lockhaven
- Lockport
- Loda
- Lodemia
- Lodge
- Logan
- Logan
- Loimbach Landing
- Lomax
- Lombard
- Lombardville
- London Mills
- Lone Tree
- Lone Tree Corners
- Long Branch
- Long Branch
- Long Creek
- Long Grove
- Long Lake
- Long Point
- Longview
- Loogootee
- Loraine
- Loran
- Lorenzo
- Loretto
- Lostant
- Lost Nation
- Lost Prairie
- Lotus
- Lotus Woods
- Louisville
- Love
- Loves Corner
- Loves Park
- Lovilla
- Lovington
- Lowder
- Lowell
- Low Point
- Loxa
- Lucas
- Ludlow
- Lumaghi Heights
- Lusk
- Luther
- Lyndon
- Lynn Center
- Lynnville
- Lynwood
- Lynwood
- Lyons