Background: Laparoscopic Roux-en-Y gastric bypass (LRYGB) is an effective treatment for achieving and maintaining weight loss and for improving obesity-related comorbidities. As part of the approval process for bariatric surgery, many insurance companies require patients to have documented recent participation in a supervised weight loss program. The goal of this study was to evaluate the relationship of preoperative weight changes with outcomes following LRYGB. Methods: A retrospective review was conducted of adult patients undergoing LRYGB between 2008 and 2012 at a single institution. Patients were stratified into quartiles based on % excess weight gain (0–4.99 % and ≥5 % EWG) and % excess weight loss (0–4.99 % and ≥5 % EWL). Generalized linear models were used to examine differences in postoperative weight outcomes at 6, 12, and 24 months. Covariates included in the final adjusted models were determined using backwards stepwise selection. Results: Of the 300 patients included in the study, there were no significant demographic differences among the quartiles. However, there was an increased time to operation for patients who gained or lost ≥5 % excess body weight (p < 0.001). Although there was no statistical significance in postoperative complications, there was a higher rate of complications in patients with ≥5 % EWG compared to those with ≥5 % EWL (12.5 vs. 4.8 %, respectively; p = 0.29). Unadjusted and adjusted generalized linear models showed no statistically significant association between preoperative % excess weight change and weight loss outcomes at 24 months. Conclusion: Patients with the greatest % preoperative excess weight change had the longest intervals from initial visit to operation. No significant differences were seen in perioperative and postoperative outcomes. This study suggests preoperative weight loss requirements may delay the time to operation without improving postoperative outcomes or weight loss.