- Isaac
- Isakson
- Isbell
- Isgrig
- Isham
- Ishmael
- Isner
- Isom
- Israel
- Iten
- Iucho
- Iuliucci
- Ivanjack
- Iversen
- Iverson
- Ives
- Ivethorn
- Ivey
- Ivie
- Ivory
- Izard
- Izon
- Izzo
- Jackett
- Jackley
- Jackman
- Jacks
- Jackson
- Jacob
- Jacobs
- Jacobsen
- Jacobson
- Jacoby
- Jacques
- Jaggers
- Jakubiak
- Jakubowski
- James
- Jamroz
- Jandrew
- Janes
- Jannaccone
- Janney
- Janosz
- Jarrell
- Jarvis
- Jaskolski
- Jaubert
- Jaussi
- Jay
- Jayne
- Jealous
- Jean-Jacques
- Jeffers
- Jeffery
- Jeffrey
- Jellye
- Jenican
- Jenison
- Jenkin
- Jenkins
- Jenks
- Jenness
- Jenney
- Jennings
- Jennison
- Jensen