This paper analyze the psychometric properties of the Spanish version of the test Procrastination Assessment Scale-Students (PASS) applied to college students in Colombia. The content and construct validity through Rasch model, the factorial validity through factor analysis of reasons to procrastinate and the discriminant validity over the analysis of the relationship with time management and grades was researched. Also, the test reliability, lenght of Likert scale and differential item functioning (DIF) was analyzed. The sample was 494 college students from nine different programs. The results indicate that the data fits the model adequately, has good values of reliability, the DIF was not found in any items, the Likert scale could be reduced from five to four categories, and five factors explained the reasons to procrastinate. Negative and significant correlations between procrastination and time management and grades was obtained.