This document evaluates GNSS code and phase solutions. It summarizes the key differences between code-only and code+phase differential GPS (DGPS) processing techniques. Code measurements are affected by biases while phase measurements also contain integer ambiguities. The document tests DGPS code and code+phase solutions using a dual-frequency GPS receiver to collect data at points within 10km of a reference station. Results show coordinate discrepancies between the two solutions are generally below 1m.