Importantly, the CID spectra of charge-inverted branched FAs derived from non-esterified FAs or from complex GPL precursor anions are identical, meaning that this workflow can be utilized to examine a diverse range of branched lipid species. Moreover, as all GPL classes can be ionized in negative ion mode, fatty acyl anions can be liberated from any GPL precursor anion regardless of headgroup composition using low-energy CID. Thus, the developed gas-phase ion/ion chemistry can be applied to unravel GPL structure, including methyl branching position, independent of the polar headgroup present, further highlighting the versatility of ion/ion platforms.