Current cosmic microwave background (CMB) bounds on the sum of the neutrino masses assume a sudden reionization scenario described by a single parameter that determines the onset of reionization. We investigate the bounds on the neutrino mass in a more general reionization scenario based on a principal component approach. We found the constraint on the sum of the neutrino masses from CMB data can be relaxed by a $sim$40% in a generalized reionization scenario. Moreover, the amplitude of the r.m.s. mass fluctuations $sigma_8$ is also considerably lower providing a better consistency with a low amplitude of the Sunyaev-Zeldovich signal.
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