Nanosecond laser flash photolysis (347.1 nm) of 2-nitrothiophen (NT) in several polar and non-polar solvents at 293 K shows a transient absorption centred at 545 ± 5 nm with Iµ= 9.8 × 103 dm3 mol–1 cm–1, which is assigned to the lowest triplet excited state of NT, denoted 3NT. Whilst λmax of 3NT does not shift with change of solvent polarity, its lifetime depends strongly on the solvent, being < 20 ns in toluene and 300 ns in acetonitrile. Triplet–triplet energy transfer experiments enabled the triplet energy, ET, to be determined as 247 ± 2 kJ mol–1. 3 NT is a reactive species, abstracting a hydrogen atom from diphenylmethanol with k2=(6.70 ± 1.09)× 107 dm3 mol–1 s–1 and an electron from 1,3,5-trimethoxybenzene with k2=(5.12 ± 0.16)× 109 dm3 mol–1 s–1, in acetone and acetonitrile solution, respectively. The standard reduction potential of 3NT is estimated to be 2.17 V vs. the standard hydrogen electrode (SHE), in aqueous solution. The observed pattern of reactivity suggests an increasing stabilisation of a π–π* triplet state in polar solvents relative to a n–π* triplet state, which is considered to be of lower energy in non-polar solvents.