- Leisure Hill
- Len Mar Community
- Lereley
- Liberty Manor
- Liberty Mobile Home Park
- Lincoln Mobile Home Park
- Linden Springs
- Linhigh
- Loch Hill
- Loch Raven
- Loch Raven Heights
- Loch Raven Village
- Locksley
- Locust Hill
- Lodge Forest
- Long Beach Estates
- Long Green Manor
- Long Green Woods
- Long Meadow West
- Long Meadows Estates
- Loveton Farms
- Lowell Ridge
- Lutherville-Timonium
- Lutz Hill
- Lynch Point
- Lynn Acres
- Lynnhurst
- Lyonswood
- Long Cove Estates
- Lake Karylbrook