Cognitive biases shown to impact medical decision‐making include left‐digit bias, the tendency to focus on a continuous variable's leftmost digit. We hypothesized that left‐digit bias impacts deceased donor kidney utilization through heuristic processing of donor age and creatinine. We used US registry data to identify 87 019 kidneys recovered (2015–2019) and compared the proportion around thresholds for donor age (69 vs. 70 years) and creatinine (1.9 vs. 2.0 mg/dl), then compared the risk of kidney discard. Kidneys from donors aged 70 vs. 69 years were more frequently discarded (77% vs. 65%, p < .001), with higher risk of discard even after adjusting for KDRI (adjusted RR 1.11, 95% CI 1.02–1.21, p = .018). Similarly, kidneys from donors with final creatinine 2.0 vs. 1.9 mg/dl were more frequently discarded (37% vs. 29%, p < .001), with higher risk of discard after adjusting for KDRI (adjusted RR 1.19, 95% CI 1.07–1.33, p = .001). However, no significant left‐digit effect was found when examining other donor age (39/40, 49/50, 59/60 years) or creatinine (0.9/1.0, 2.9/3.0 mg/dl) thresholds. The findings suggest a possible left‐digit effect affecting kidney utilization at specific thresholds. Additional investigations of the impact of this and other heuristics on organ utilization are needed to identify potential areas for decision‐making interventions aimed at reducing kidney discard.