Background: Postprandial lipemia (PPL) is predictive of cardiovascular disease risk. However, the current method for assessing PPL is a burdensome process. Recently, the validity of an abbreviated fat tolerance test (AFTT) has been established. As a continuation of this research, the purpose of this study was to determine whether the AFTT is reliable and compare it to the reliability of the oral glucose tolerance test (OGTT). Methods: In this randomized crossover trial, twenty healthy adults (10 male and 10 female) completed two AFTTs and two OGTTs separated by a one week washout period. For the AFTT, triglycerides (TG) were measured at baseline and 4 hours after a high-fat meal, during which time participants were able to leave the lab. The OGTT involved measurement of glucose at baseline and 2-hours post-consumption of a 75-gram glucose drink, and participants remained in the lab. To determine reliability, we calculated within-subject coefficient of variation (WCV) and intraclass correlation coefficient (ICC). Results: The mean 4-hour TG WCV for the AFTT was 12.6%, while the mean 2-hour glucose WCV for the OGTT was 10.5%, indicating similar reliability for both tests. ICC values for 4-hour TG and TG change were >0.7 and higher than ICC values for 2-hour and glucose change, indicating good reliability. Conclusion: The AFTT was observed to be similarly reliable to the OGTT, supporting its potential as a standard clinical test for determining PPL. Further clinical trials are needed to establish its true utility.