Experimental data on the characterisation of stress-induced depolarisation in a DiPOLE 100J 10Hz amplifier as a function of optics in the beam path, pumping power, mass flow rate, input polarisation state. Data refers to single pass measurements.Royal Commission for the Exhibition of 1851 (Industrial Fellowship); Laserlab-Europe (654148);Engineering and Physical Sciences Research Council (1979259); European Union’s Horizon2020 (739573).