| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Rector | city | California | United States | 36.31 | -119.24 | 298 | |
| Red Apple | city | California | United States | 38.18 | -120.38 | 3349 | |
| Red Arrow Mobile Home Park | city | California | United States | 37.66 | -122.44 | 196 | |
| Red Bank | city | California | United States | 40.10 | -122.45 | 830 | |
| Red Bluff | city | California | United States | 40.18 | -122.24 | 314 | |
| Red Dog | city | California | United States | 39.22 | -120.90 | 2795 | |
| Red Fir | city | California | United States | 36.61 | -118.77 | 7043 | |
| Red Mountain | city | California | United States | 35.36 | -117.62 | 3654 | |
| Red Point (historical) | city | California | United States | 39.15 | -120.70 | 4199 | |
| Redbanks | city | California | United States | 36.42 | -119.14 | 830 | |
| Redbud Park (historical) | city | California | United States | 38.52 | -122.14 | 830 | |
| Redcrest | city | California | United States | 40.40 | -123.95 | 830 | |
| Redding | city | California | United States | 40.59 | -122.39 | 830 | |
| Redding Lakeside Mobile Estates | city | California | United States | 40.71 | -122.34 | 994 | |
| Redding Oaks Mobile Home Park | city | California | United States | 40.53 | -122.39 | 830 | |
| Reddingwood Mobile Home Park | city | California | United States | 40.55 | -122.39 | 830 | |
| Redlands | city | California | United States | 34.06 | -117.18 | 1669 | |
| Redlands Heights | city | California | United States | 34.03 | -117.16 | 1833 | |
| Redman | city | California | United States | 34.76 | -117.97 | 2509 | |
| Redondo Beach | city | California | United States | 33.85 | -118.39 | 52 | |
| Redondo Junction | city | California | United States | 34.02 | -118.23 | 196 | |
| Redrock (historical) | city | California | United States | 35.35 | -117.97 | 2509 | |
| Redway | city | California | United States | 40.12 | -123.82 | 400 | |
| Redwood City | city | California | United States | 37.49 | -122.24 | 68 | |
| Redwood City Mobile Home Park | city | California | United States | 37.49 | -122.21 | 45 | |
| Redwood Corral | city | California | United States | 35.98 | -118.66 | 6072 | |
| Redwood Estates | city | California | United States | 37.16 | -121.99 | 1233 | |
| Redwood Grove | city | California | United States | 37.16 | -122.13 | 830 | |
| Redwood Heights | city | California | United States | 37.80 | -122.19 | 410 | |
| Redwood Junction | city | California | United States | 37.48 | -122.22 | 98 | |
| Redwood Lakanbalen | city | California | United States | 37.49 | -122.24 | 68 | |
| Redwood Lodge | city | California | United States | 39.44 | -123.69 | 830 | |
| Redwood Lodge | city | California | United States | 37.11 | -121.94 | 1669 | |
| Redwood Mobile Home Park | city | California | United States | 37.49 | -122.20 | 29 | |
| Redwood Park | city | California | United States | 37.43 | -122.32 | 1669 | |
| Redwood Shores | city | California | United States | 37.53 | -122.25 | 6 | |
| Redwood Terrace | city | California | United States | 37.31 | -122.29 | 396 | |
| Redwood Trailer Village | city | California | United States | 37.48 | -122.20 | 68 | |
| Redwood Valley | city | California | United States | 39.27 | -123.20 | 830 | |
| Redwoods | city | California | United States | 40.60 | -121.94 | 1998 | |
| Redwoods Mobile Home Community | city | California | United States | 40.62 | -122.38 | 830 | |
| Reed | city | California | United States | 37.90 | -122.50 | 196 | |
| Reedley | city | California | United States | 36.60 | -119.45 | 298 | |
| Reeds (historical) | city | California | United States | 35.18 | -120.59 | 830 | |
| Reef Station | city | California | United States | 35.90 | -120.05 | 830 | |
| Reefer City (historical) | city | California | United States | 35.01 | -118.19 | 2798 | |
| Reeves Place | city | California | United States | 39.89 | -123.11 | 2811 | |
| Reeves Place | city | California | United States | 35.16 | -120.31 | 1213 | |
| Regal Mobile Club Estates | city | California | United States | 33.64 | -117.94 | 95 | |
| Regina Heights | city | California | United States | 39.15 | -123.17 | 849 | |
| Reilly (historical) | city | California | United States | 36.01 | -117.37 | 2509 | |
| Reilly Heights | city | California | United States | 39.11 | -123.52 | 396 | |
| Reka (historical) | city | California | United States | 36.69 | -119.55 | 298 | |
| Rekwoi (historical) | city | California | United States | 41.54 | -124.05 | 59 | |
| Relief | city | California | United States | 39.36 | -120.86 | 3628 | |
| Remillard (historical) | city | California | United States | 37.67 | -121.85 | 380 | |
| Remington Hill (historical) | city | California | United States | 39.28 | -120.79 | 3595 | |
| Remnoy | city | California | United States | 36.34 | -119.55 | 196 | |
| Rendalia | city | California | United States | 33.89 | -118.13 | 45 | |
| Reno Junction | city | California | United States | 39.79 | -120.10 | 5246 | |
| Renoville | city | California | United States | 35.55 | -116.19 | 830 | |
| Renshaw Place | city | California | United States | 35.17 | -120.26 | 1669 | |
| Requa | city | California | United States | 41.55 | -124.07 | 91 | |
| Reseda | city | California | United States | 34.20 | -118.54 | 830 | |
| Reward | city | California | United States | 36.75 | -118.06 | 4189 | |
| Reward | city | California | United States | 35.32 | -119.68 | 1669 | |
| Rex | city | California | United States | 34.95 | -120.38 | 396 | |
| Rex Manor | city | California | United States | 37.41 | -122.09 | 72 | |
| Reyes Place | city | California | United States | 39.85 | -123.41 | 1669 | |
| Reynolds | city | California | United States | 38.15 | -122.88 | 157 | |
| Reynolds (historical) | city | California | United States | 36.23 | -119.07 | 390 | |
| Reynolds (historical) | city | California | United States | 39.94 | -123.78 | 830 | |
| Reynolds Place (historical) | city | California | United States | 39.67 | -122.71 | 3579 |