Background and Objectives: Metabolic syndrome (MetS) is considered a global epidemic, and its diagnosis is crucial, allowing early intervention and management. The main aim of this study was to examine any possible blood pressure (BP) differences based on office and out-of-office measurements in patients with and without MetS, and to investigate if any of these measurements correlated better with MetS. The secondary aim was to investigate any possible cardiovascular risk differences. Materials and Methods: The study population consisted of individuals attending the outpatient hypertension clinic. Office and out-of-office BP measurements were recorded in all of the patients, as well as different cardiovascular risk scores and echocardiography. MetS was defined according to ACC/AHA criteria. Results: A total of 282 (39.9% men) individuals (56.8 ± 15.8 years) were analyzed; 60.8% of them had MetS. The patients with MetS had a significantly higher systolic BP (SBP) in all of the BP measurements, higher ASCVD risk (22% vs. 12%), Framingham risk scores (11.8% vs. 6.9%), a significantly higher prevalence of LVH (49.2% vs. 22.7%) and early vascular aging (54.8% vs. 27.4%) compared with the patients without MetS (p < 0.05 for all). In a univariate analysis, MetS was significantly correlated with the average 24h SBP, daytime and nighttime ambulatory SBP, office SBP, and home SBP in the morning (p < 0.05). No significant differences were observed for any of the DBP measurements. Finally, 50.5% of the MetS patients had sustained hypertension, 15.2% masked hypertension, and 11.5% white-coat hypertension based on ABPM, and these values were 45.1%, 19.3%, and 13.6%, respectively, based on HBPM. Furthermore, most of the MetS patients had non-dipping hypertension (56.4%). Conclusions: The present findings highlight the importance of out-of-office BP measurements in the diagnosis of MetS, since both a high office and out-of-office SBP were significant features of the syndrome (whereas this was not the case with DBP). This is further supported by the increased prevalence of different hypertension phenotypes observed in the MetS patients. Higher ASCVD risk scores and LVH and EVA prevalence were also related to MetS, thus strongly supporting the necessity for early detection and treatment.