Abstract: There is limited information regarding the performance of Stand-Up Paddleboard (SUP) technology and the means to evaluate its performance. The aim of this study was to assess the intra-test reliability of a proposed outdoor field assessment methodology and three different levels of SUP technology. These included changes made to the board, the paddle or the fin and to assess their performance and statistical reliability. A participant completed a series of randomised runs at 2.5 m/sec over a 230 m distance on three separate test events all held at a flat water test venue. The stroke index was used to evaluate each technological change made to the paddler’s equipment. All three test events yielded a good level of reliability (Coefficient of Variation = <2.4%). The proposed assessment method was also able to detect seven out of eight prescribed technological changes with statistical significance (p = 0.05). As a result, the proposed assessment method is recommended as a specific, geographically accessible and cost effective means of SUP technological assessment.