The value of the viscosity B-coefficient of the thiocyanate anion reported in the biophysical literature, B-n(SCN-) = -0.103 dm(3).mol(-1), is erroneous. It is not derived from direct viscosity measurements. It should be replaced by -0.032 +/- 0.006 dm(3).mol(-1) at 25 degrees C, the average from values derived from viscosity measurements.