By means of an exhaustive spectroscopic and computational characterisation, we have revealed a common, direct SET from multiple anionic organic bases to nitrobenzene to afford the facile formation of [1 •-]([X + ]) ion pairs -this is fundamentally different from previous reports where SET is mediated by an intermediate anion. For t BuLi and LDA bases, the direct SET is an exothermic process that occurs readily. For Na iPr Cp, XO t Bu, and XHMDS (X = Li, Na, K), it is slightly endothermic, with further transformations of the oxidised base, such as dimerization and/or HAT of solvent molecules, rendering the whole process thermally accessible. This interpretation is further supported by the absence of other radical species in all our EPR spectra, and the fact that reaction of [1] with the Bronsted base TBD does not yield any radical (Scheme S11, Table ). For XO t Bu and XHMDS (X = Li, Na), and depending on the reaction conditions, we observe non-stoichiometric ratios between [1 •-] and the number of equivalent I=3/2 nuclear spins needed to fit the EPR data, which is tentatively assigned to aggregate formation. ) is formed regardless of the conditions employed, but adding a chelating agent to force a separated ion pair has proven to be the most efficient strategy to gain spectral resolution and obtain reliable model spin Hamiltonian parameters. We have also shown that salt dissociation favours SET, offering a handle towards controlling the amount of generated radical species by an appropriate choice of the medium. Other reaction mechanisms for [1 •-]([X + ]) formation were explored using DFT calculations, but deemed thermodynamically less competitive than the direct SET.