| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| J Diamond Trailer and Recreational Vehicle Park | city | California | United States | 37.37 | -118.40 | 4199 | |
| Jacinto | city | California | United States | 39.58 | -122.01 | 98 | |
| Jacksnipe | city | California | United States | 38.19 | -122.07 | 3 | |
| Jackson | city | California | United States | 38.35 | -120.77 | 1669 | |
| Jackson Park | city | California | United States | 37.40 | -122.08 | 91 | |
| Jacobs Corner | city | California | United States | 38.67 | -121.89 | 118 | |
| Jacobsen (historical) | city | California | United States | 39.01 | -120.39 | 6036 | |
| Jacumba Hot Springs | city | California | United States | 32.62 | -116.19 | 2831 | |
| Jalama | city | California | United States | 34.50 | -120.49 | 396 | |
| Jalama (historical) | city | California | United States | 34.51 | -120.50 | 118 | |
| Jamacha | city | California | United States | 32.74 | -116.91 | 830 | |
| Jamacha Junction | city | California | United States | 32.74 | -116.94 | 331 | |
| James | city | California | United States | 39.65 | -121.55 | 1174 | |
| Jamesan | city | California | United States | 36.72 | -120.21 | 170 | |
| Jamesburg | city | California | United States | 36.37 | -121.59 | 1968 | |
| Jamestown | city | California | United States | 37.95 | -120.42 | 1669 | |
| Jamison (historical) | city | California | United States | 39.78 | -120.68 | 5055 | |
| Jamul | city | California | United States | 32.72 | -116.88 | 1020 | |
| Jamul Indian Village | city | California | United States | 32.71 | -116.87 | 990 | |
| Janes Place | city | California | United States | 40.79 | -123.72 | 3349 | |
| Janesville | city | California | United States | 40.30 | -120.52 | 4251 | |
| Jarvis Landing | city | California | United States | 37.53 | -122.06 | 42 | |
| Jasmin | city | California | United States | 35.74 | -119.14 | 830 | |
| Jastro | city | California | United States | 35.38 | -119.07 | 390 | |
| Java | city | California | United States | 34.89 | -114.73 | 1043 | |
| Jayhawk | city | California | United States | 38.73 | -120.97 | 1204 | |
| Jefferson | city | California | United States | 34.02 | -118.27 | 187 | |
| Jefferson Park | city | California | United States | 34.03 | -118.32 | 173 | |
| Jellico | city | California | United States | 40.84 | -121.29 | 5203 | |
| Jenks Place | city | California | United States | 39.71 | -122.85 | 5869 | |
| Jenner | city | California | United States | 38.45 | -123.12 | 3 | |
| Jenny Lind | city | California | United States | 38.09 | -120.87 | 298 | |
| Jerome | city | California | United States | 41.73 | -122.00 | 4347 | |
| Jerseydale | city | California | United States | 37.56 | -119.86 | 4189 | |
| Jesbel (historical) | city | California | United States | 37.15 | -119.95 | 830 | |
| Jesmond Dene | city | California | United States | 33.18 | -117.11 | 997 | |
| Jesus Maria | city | California | United States | 38.29 | -120.65 | 1669 | |
| Jet | city | California | United States | 37.43 | -121.10 | 111 | |
| Jewell | city | California | United States | 38.04 | -122.75 | 196 | |
| Jim Leggett Place | city | California | United States | 39.86 | -123.42 | 2080 | |
| Jimgrey | city | California | United States | 34.98 | -117.47 | 2509 | |
| Jims Camp | city | California | United States | 41.83 | -122.59 | 2575 | |
| Jimtown | city | California | United States | 38.67 | -122.82 | 196 | |
| Joes Landing | city | California | United States | 38.78 | -121.60 | 19 | |
| Joesphine | city | California | United States | 39.09 | -121.80 | 29 | |
| Jofegan | city | California | United States | 33.32 | -117.33 | 196 | |
| Johannesburg | city | California | United States | 35.37 | -117.63 | 3549 | |
| Johnson Corner | city | California | United States | 34.31 | -117.75 | 4189 | |
| Johnson Park | city | California | United States | 40.92 | -121.63 | 3349 | |
| Johnsondale | city | California | United States | 35.97 | -118.54 | 5029 | |
| Johnsons | city | California | United States | 41.35 | -123.87 | 200 | |
| Johnston Corner | city | California | United States | 36.93 | -121.71 | 49 | |
| Johnstons Corner | city | California | United States | 34.83 | -117.18 | 2509 | |
| Johnstonville | city | California | United States | 40.38 | -120.59 | 4189 | |
| Johnstown | city | California | United States | 32.84 | -116.90 | 830 | |
| Johnsville | city | California | United States | 39.76 | -120.70 | 5869 | |
| Johnsville Mobile Home Park | city | California | United States | 37.41 | -121.90 | 55 | |
| Jolon | city | California | United States | 35.97 | -121.18 | 925 | |
| Jonata Park | city | California | United States | 34.65 | -120.18 | 830 | |
| Jones Bar (historical) | city | California | United States | 39.29 | -121.11 | 1669 | |
| Jones Corner | city | California | United States | 36.07 | -119.11 | 393 | |
| Jones Place | city | California | United States | 38.85 | -120.37 | 5029 | |
| Jonesville | city | California | United States | 40.11 | -121.47 | 5347 | |
| Jorbalinda | city | California | United States | 33.89 | -117.81 | 396 | |
| Jordan Downs | city | California | United States | 33.95 | -118.23 | 98 | |
| Jordan Park | city | California | United States | 37.78 | -122.46 | 347 | |
| Joshua | city | California | United States | 35.27 | -115.45 | 4189 | |
| Joshua Tree | city | California | United States | 34.13 | -116.31 | 2778 | |
| Jovista | city | California | United States | 35.80 | -119.18 | 400 | |
| Juan | city | California | United States | 35.37 | -115.09 | 4294 | |
| Julian | city | California | United States | 33.08 | -116.60 | 4396 | |
| Junction Camp | city | California | United States | 34.73 | -119.98 | 3366 | |
| Junction City | city | California | United States | 40.73 | -123.05 | 1669 | |
| Junction House | city | California | United States | 39.32 | -120.81 | 4399 | |
| Junction House | city | California | United States | 39.74 | -121.29 | 3369 | |
| Junction Ranch | city | California | United States | 36.07 | -117.51 | 5869 | |
| June Lake | city | California | United States | 37.78 | -119.08 | 7972 | |
| June Lake Junction | city | California | United States | 37.81 | -119.05 | 7811 | |
| Juniper | city | California | United States | 41.48 | -120.57 | 4340 | |
| Juniper Hills | city | California | United States | 34.44 | -117.94 | 4494 | |
| Juniper Springs | city | California | United States | 33.77 | -117.08 | 2509 | |
| Jupiter | city | California | United States | 38.12 | -120.28 | 2913 |