For the 2021-22 season, Division III realigned basketball into 10 regions. Region 10 is primarily teams from the "island" areas of the west coast and southwest. To find other former West Region teams such as the ARC, MIAC and UMAC, check out Region 9 and to find other former South Region teams such as the ODAC, SAA and USAC, check out Region 6.
| School | Location | Conference | Enrollment |
| Austin | Sherman, TX | SCAC | 1204 |
| Cal Lutheran | Thousand Oaks, CA | SCIAC | 2001 |
| Caltech | Pasadena, CA | SCIAC | 977 |
| Centenary (La.) | Shreveport, LA | SCAC | 869 |
| Chapman | Orange, CA | SCIAC | 4069 |
| Claremont-Mudd-Scripps | Claremont, CA | SCIAC | 2873 |
| Colorado College | Colorado Springs, CO | SCAC | 2034 |
| Concordia (Texas) | Austin, TX | ASC | 1205 |
| East Texas Baptist | Marshall, TX | ASC | 1093 |
| George Fox | Newberg, OR | NWC | 2108 |
| Hardin-Simmons | Abilene, TX | ASC | 1743 |
| Howard Payne | Brownwood, TX | ASC | 1042 |
| La Verne | La Verne, CA | SCIAC | 3106 |
| LeTourneau | Longview, TX | ASC | 1329 |
| Lewis and Clark | Portland, OR | NWC | 1911 |
| Linfield | McMinnville, OR | NWC | 1659 |
| Mary Hardin-Baylor | Belton, TX | ASC | 3112 |
| McMurry | Abilene, TX | ASC | 951 |
| Occidental | Los Angeles, CA | SCIAC | 1826 |
| Pacific Lutheran | Tacoma, WA | NWC | 3109 |
| Pacific | Forest Grove, OR | NWC | 1402 |
| Pomona-Pitzer | Claremont, CA | SCIAC | 2515 |
| Puget Sound | Tacoma, WA | NWC | 2536 |
| Redlands | Redlands, CA | SCIAC | 2786 |
| Schreiner | Kerrville, TX | SCAC | 1035 |
| Southwestern | Georgetown, TX | SCAC | 1237 |
| St. Thomas (Texas) | Houston, TX | SCAC | 2000 |
| Sul Ross State | Alpine, TX | ASC | 1285 |
| Texas Lutheran | Seguin, TX | SCAC | 1307 |
| Texas-Dallas | Richardson, TX | ASC | 17968 |
| Trinity (Texas) | San Antonio, TX | SCAC | 2439 |
| UC Santa Cruz | Santa Cruz, CA | C2C | 17052 |
| University of Dallas | Dallas, TX | SCAC | 1255 |
| University of the Ozarks | Clarksville, AR | ASC | 545 |
| Whitman | Walla Walla, WA | NWC | 1507 |
| Whittier | Whittier, CA | SCIAC | 1366 |
| Whitworth | Spokane, WA | NWC | 2116 |
| Willamette | Salem, OR | NWC | 1746 |