Simultaneous pancreas-kidney transplantation (SPK) carries about a 7%–22% risk of technical failure, but the impact of early pancreas allograft loss on subsequent kidney graft and patient survival is not well-defined. We examined national transplant registry data for type 1 diabetic patients who received SPK between 2000 and 2021. Associations of transplant type (i.e., SPK, deceased‐donor kidney transplant [DDKA], living‐donor kidney transplant [LDKA]) with kidney graft failure and patient survival were estimated by multivariable inverse probability of treatment-weighted accelerated failure-time models. Compared to SPK recipients with a functioning pancreas graft 3 months posttransplant (SPK,P+), LDKA had 18% (Time Ratio [TR] 0.82, 95%CI: 0.70–0.95) less graft survival time and 18% (TR 0.82, 95%CI: 0.68–0.97) less patient survival time, DDKA had 23% (TR 0.77, 95%CI: 0.68–0.87) less graft survival time and 29% (TR 0.71, 95%CI: 0.62–0.81) less patient survival time, and SPK with early pancreas graft loss had 34% (TR 0.66, 95%CI: 0.56–0.78) less graft survival time and 34% (TR 0.66, 95%CI: 0.55–0.79) less patient survival time. In conclusion, SPK,P+ recipients have better kidney allograft and patient survival compared with LDKA and DDKA. Early pancreas graft failure results in inferior kidney and patient survival time compared to kidney transplant alone.