- Railroad Commission of Washington2
- Rand Avery Supply Co2
- Rawdon, Clark & Co.2
- Real Estate Title and Trust Co. (Portland, Or.)2
- Reckless, Walter C., 1899-19882
- Reuben H. Donnelley Corporation2
- Reynolds, James, active 1845-1864.2
- Rinker, Andrew2
- Risser, Michele.2
- Road Commission2
- Roberts, W. A. (Soil surveyor)2
- Roeser, C. (Charles)2
- Roeser, Charles2
- Rogers, F. Kimball2
- Rominger, Carl Ludwig, 1820-19072
- Royal Geographical Society (Great Britain)2
- Ruger, A.2
- Runkel, A.C2
- Rutgers University Cartography Laboratory, Department of Geography2
- S. Lewis and Co. (London, England)2