Background: Vericiguat is indicated for the treatment of symptomatic chronic heart failure in adult patients with reduced ejection fraction who are stabilized after a recent decompensation event. Objective: To investigate the effects of vericiguat on QT interval in patients with chronic coronary syndromes (CCS). Methods: This was a randomized, phase Ib, placebo-controlled, double-blind, double-dummy, multicenter study. Vericiguat once daily was up-titrated from 2.5 mg to 5 mg and then to 10 mg (treatments A, B, and C) at 14-day intervals. Positive control was moxifloxacin 400 mg (single dose on day 8 or day 50; placebo on other days [treatment D]). We evaluated the placebo-adjusted change from baseline of the Frederica-corrected QTc interval (QTcF), pharmacokinetics, safety, and tolerability of vericiguat. Results: In total, 74 patients with CCS, with mean (standard deviation) age 63.4 (8.0) years, were included and 72 patients completed the study. At each timepoint up to 7 h after administration, mean placebo-corrected change in QTcF from baseline was < 6 ms and the upper limit of the two-sided 90% confidence interval of the mean was below the 10-ms threshold for clinical relevance. Moxifloxacin confirmed the assay sensitivity. Median time of maximum concentration of vericiguat was 4.5 h post-dose. The adverse event profile of vericiguat was consistent with its mechanism of action, and the findings did not indicate any safety concerns. Conclusions: As part of an integrative risk assessment, this study demonstrated no clinically relevant corrected QT prolongation with vericiguat 10 mg once daily at steady state. Clinical Trial Registration: ClinicalTrials.gov number, NCT03504982. Graphical Abstract: [Figure not available: see fulltext.]