The ternary liquid-liquid equilibria for four systems containing an alcohol (1-propanol or 1-butanol) or acetic acid + ester + the ionic liquid 1-ethyl-3-methylimidazolium hydrogen sulfate [EMIM][HSO(4)] were studied at (313.2 +/- 0.5) K. In this paper, we investigated the effect of the alkyl chain on the alcohol and ester on the phase equilibria for these systems containing reactants and products of esterification reactions. The measurements were done by headspace gas chromatography. All studied systems are of type I, with ester and [EMIM][HSO(4)] as the only immiscible pair. The increase of the alkyl chain length on alcohol and ester leads to bigger immiscibility regions and better solubility of the alcohol in the ester phase. The distribution of the acetic acid between the two phases is almost independent of the esters for the measured systems and is dependent mainly on the ionic liquid. The obtained information on the influence of the alkyl chain on the equilibrium can be used to roughly estimate the behavior of unknown systems as illustrated on several examples.