Ages effective for the 2026-27 GTHL season. Player ages are determined by age as of December 31, 2026.
| CATEGORY | BIRTHDATES |
| U21 | Born in 2006, 2007, and 2008 |
| U18 | Born in 2009-2010 |
| U17 | Born in 2010 |
| U16 | Born in 2011 |
| U15 | Born in 2012 |
| U14 | Born in 2013 |
| U13 | Born in 2014 |
| U12 | Born in 2015 |
| U11 | Born in 2016 |
| U10 | Born in 2017 |
| U9 | Born in 2018 |
| U8 | Born in 2019 |
| U7 | Born in 2020 |
| U6 | Born in 2021 |
| U5 | Born in 2022 |
