The natural history of back pain in patients awaiting elective lumbar spine surgery within a public healthcare system remains incompletely characterised. Understanding how pain evolves over the preoperative waiting period is relevant for resource allocation and the targeting of preoperative interventions. This prospective single-centre cohort study examined back pain trajectories over a six-month waiting period in 40 consecutive patients (mean age 64.7 years; 42.5% male) listed for elective lumbar spine surgery at an Australian public tertiary orthopaedic unit between October 2022 and October 2024. Pain severity was assessed using the Visual Analog Scale across motion, standing, and sitting domains and the 36-Item Short Form Health Survey at recruitment and at six months. Paired analysis demonstrated no statistically or clinically significant change in mean VAS scores across any domain, with mean changes of approximately 0.2 points in all domains and the composite (all p > 0.5). Using a 2-point minimum clinically important difference threshold, 70% of patients (28/40) had no meaningful change, 15% (6/40) improved, and 15% (6/40) worsened. SF-36 results triangulated this finding: no subscale or component summary score showed a statistically significant change over six months. These findings indicate that, contrary to the prevailing assumption, mean preoperative pain remains stable for most patients during a six-month wait, while a minority subgroup deteriorates. The results extend recent international evidence to the Australian public-system context and support a shift toward identifying and targeting patients at risk of meaningful preoperative deterioration rather than universal preoperative interventions.