| Steve Langford | Glen Ellyn | IL | Approved | 20203 | Grade 4 Senior (18 and over) | Grade 4 | | | | | | |
| Aaron Lankford | Brownsburg | Indiana | Approved | 26011 | Grade 4 Senior (18 and over) | (none) | | | | | | |
| Betsy LaRocco | Laporte | IN | Approved | 25045 | Practice Chanter Novice (all ages) | | | | | | | |
| Stephen Lash | Westlake | OH | Approved | 26133 | Open | | | | | | | |
| Jacob Layrock | Beebe | Arkansas | Approved | 20924 | Grade 1 | Grade 1 | | | | | | |
| Chris Layton | Overland Park | Kansas | Approved | 25068 | Grade 4 Senior (18 and over) | Grade 4 | | | | | | |
| Chris Layton | Overland Park | KS | Approved | 25068 | Grade 4 Senior (18 and over) | Grade 4 | | | | | | |
| Liam Leasure | St Paul | MN | Approved | 20174 | | | Grade 2 | | | | | |
| Rosie Leasure | Grinnell | IA | Approved | 20822 | | | Grade 4 | | | | | |
| Alex Lee | Canonsburg | PA | Approved | 26077 | | | Grade 2 | | | | | |
| Andrew Lewis | Vadnais Heights | MN | Approved | 20162 | Open | Open | Grade 4 | (none) | (none) | (none) | Register as an Adjudicator | |
| Benjamin Locker | Clawson | MI | Approved | 20369 | Grade 5 Junior (under 18) | Grade 4 | | | | | | |
| Andrew Lockwood | Bloomington | IL | Approved | 26131 | | | | | | | | Register as a Supporting Member |
| Freddrick Long | Weatherford | Texas | Approved | 20838 | Grade 4 Senior (18 and over) | Grade 4 | | | | | | |
| Russell Loucks | River Falls | Wisconsin | Approved | 20919 | | | | Novice | Novice | | | |
| Jessie Lu | Minneapolis | MN | Approved | 25066 | Grade 4 Senior (18 and over) | | | | | | | |
| Sydney Lybert | Pulaski | Wisconsin | Approved | 20929 | Grade 3 | Grade 3 | | | | | | |
| Matthew Lydon | Wheaton | IL | Approved | 26125 | Grade 5 Senior (18 and over) | (none) | | | | | | |
| Steve MacDougall | Roscoe | Illinois | Approved | 20287 | (none) | (none) | Grade 4 | (none) | (none) | (none) | | |
| Colum MacKinnon | Minnetonka | MN | Approved | 20114 | Grade 4 Senior (18 and over) | Grade 4 | | | | | | |
| Steven MacLeod | Henrietta | NY | Approved | 20058 | Grade 2 | Grade 2 | | | | | | |
| Calum MacNeil | Dearborn | MI | Approved | 20036 | Grade 1 | Grade 1 | | | | | | |
| Stephen MacNeil | Brethren | michigan | Approved | 26092 | | | | | | | Register as an Adjudicator | |
| Luke Marinelli | Medina | OH | Approved | 26015 | Grade 3 | Grade 3 | | | | | | |
| Susan Martin | Mc Intire | IA | Approved | 20031 | Grade 4 Senior (18 and over) | Grade 4 | | | | | | |
| Susan Martin | Mc Intire | IA | Approved | 20031 | Grade 4 Senior (18 and over) | Grade 4 | | | | | | |
| Susan Martin | Mc Intire | IA | Approved | 20031 | Grade 4 Senior (18 and over) | Grade 4 | | | | | | |
| Crosby Marty | Amherst | OH | Approved | 26075 | | | Grade 4 | | | | | |
| Sebastian Mattern | Brimfield | IL | Approved | 26003 | Grade 4 Junior (under 18) | Grade 4 | | | | | | |
| David May | Walled Lake | MI | Approved | 20366 | Grade 4 Senior (18 and over) | | | | | | | |