- Ladder-backed Woodpecker
- Lapland Longspur
- Lark Bunting
- Lark Sparrow
- Laughing Gull
- Lawrence's Goldfinch
- Lazuli Bunting
- Least Flycatcher
- Least Grebe
- Least Sandpiper
- Least Tern
- LeConte's Sparrow
- LeConte's Thrasher
- Lesser Goldfinch
- Lesser Scaup
- Lesser Yellowlegs
- Lewis's Woodpecker
- Limpkin
- Lincoln's Sparrow
- Little Blue Heron
- Loggerhead Shrike
- Long-billed Curlew
- Long-billed Dowitcher
- Long-billed Thrasher
- Louisiana Waterthrush