| Abbreviation | Definition |
|---|---|
| TOMWC | Tip Of the Mitt Watershed Council |
| TOP | The Ocean Project |
| TOPS | Take Off Pounds Sensibly |
| TOPS | Top One Percent Society |
| TOR | Fundasaun Timor Hari'I |
| TOS | Tree Of Savior |
| TOWF | Torch Of Wisdom Foundation |
| TPC | Tradition Pride Class |
| TPC | Traprock Peace Center |
| TPCF | Twin Pines Cooperative Foundation |
| TPCH | Todd Phillips Children's Home |
| TPCI | Turning Point Craft Initiative |
| TPF | The Peregrine Fund |
| TPHA | Texas Public Health Association |
| TPI | The Philanthropic Initiative |
| TPIF | Tulsa Project Impact Foundation |
| TPIMS | Torrey Pines Institute for Molecular Studies |
| TPJ | Texans for Public Justice |
| TPL | Trust for Public Land |
| TPOCC | Trans People Of Color Collective |