Campylobacter jejuni is a leading cause of acute gastroenteritis in developed countries, and was the first prokaryote demonstrated to extensively modify proteins by N-linked glycosylation. This highly conserved post-translational modification system is crucial for pathogenicity, albeit the mechanism remains to be elucidated. With over 120 modified sites identified to date, recent findings have suggested that N-glycosylation may be important for protein stability in various physiological and pathogenically relevant contexts. To explore this further, we employed iTRAQ-based labelling to determine the effect of either loss of the oligosaccharyltransferase (ΔpglB), or biosynthesis of the glycan (ΔpglDEF) on whole protein abundance in a relatively recent clinical isolate, C. jejuni JHH1. Of the 1077 C. jejuni proteins quantified, only 57 were deemed to have a significant change in abundance in either of the Δpgl strains relative to the wild-type isolate. A large proportion of known glycoproteins were quantified with ~17% displaying an altered abundance in the N-glycosylation negative strains. N-terminal amine isotopic labelling of substrates (N-TAILS) was also employed for pair wise comparisons of the N-degradome of wild-type JHH1 and individual pgl deletion strains to address the hypothesis that the N-linked glycan may provide protection from proteolytic degradation. We were able to identify and quantify 4122 unique N-termini from 766 C. jejuni proteins. From those derived from known N-linked glycoproteins, a number were found to be in close proximity to or contained the sites of N-linked glycosylation and in turn displayed a significant difference in their relative abundance in the Δpgl mutants. Further, we coupled N-TAILS to intact N-glycopeptide analyses to identify putative N-terminal N-glycopeptides. These proteomics-based approaches were complemented with various standard phenotypic tests to establish how the loss of N-glycosylation extended to broader changes in C. jejuni physiology.