ABSTRACT Introduction Healthcare financing models significantly impact health outcomes across many diseases in high‐income countries (HICs). In low or middle‐income countries (LMICs), where financial vulnerabilities are much higher, little is known about the relationship between payment mechanisms and emergency care outcomes. This study aimed to quantify the association between trauma care payment mechanisms and inpatient mortality. Methods We conducted analysis of data from in four facilities in province Sindh, Pakistan (two urban and two rural sites) collected between May 2023 and February 2025. The outcomes were inpatient mortality and length of stay (LOS). We compared patients with out‐of‐pocket (OOP) expenses with no‐OOP. We calculated adjusted odds ratio with a 95% confidence interval for OOP after controlling for age, sex, injury severity (Kampala Trauma Score [KTS]), blood transfusion, procedure, comorbidity, and setting. We also applied propensity score matching (PSM) on age, sex, mechanism of injury, injury severity (KTS), and setting. Results Most of the 3572 enrolled patients were young (median age 35 years and IQR 25–50) males (81.95%) and a third paid OOP for hospital care ( n = 978 and 37.38%). The overall mortality rate was 4.85%, with a significantly higher mortality rate among the OOP group compared to the no‐OOP group (10.02% vs. 2.89%; AOR 3.14: 95% CI 1.93, 5.10). Additionally, the hospital LOS (median 4 vs. 9 days and p value < 0.001) and mean survival time of patients (22.81 days vs. 28.67 and p value < 0.001) were lower for the OOP group than no‐OOP group. The odds ratio after PSM showed a weak significant independent association between OOP and mortality (OR 1.05; 95% CI 1.02, 1.08). Conclusion Patients who paid OOP for injury care had greater mortality, suggesting that alternative financing strategies could improve outcomes in LMICs. Additionally, OOP was associated with shorter LOS, highlighting the need to improve universal health coverage for complete injury care.