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The number of different sensors available for measuring soil water content has increased since the introduction of time domain reflectometry (TDR). In this study the performances of the CS616 (Campbell Scientific, Ltd., Shepshed, UK) sensor and the Aquaflex (Streat Instruments., Ltd, Christchurch, NZ) sensor were compared with TDR using both vertically and horizontally installed sensors. It was found that the CS616 manufacturer's standard calibration needed to be linearly transformed, y= 0.59x+ 0.01 (m 3 m− 3), to obtain accurate measurements in a sandy soil with horizontally installed probes. In two different soils the standard calibration performed better, and smaller corrections were found, y= 0.87x− 0.01 for a sandy loam and y= 0.96x− 0.001 (m 3 m− 3) for a sandy loam with a larger clay content, respectively. The CS616 sensor was most likely affected by electrical conductivity at 1.6 dS m− 1 in the soil solution …