Background: Chronic kidney disease (CKD) is a common medical problem in patients worldwide, with an increasing prevalence of patients with end-stage kidney disease (ESKD) requiring renal replacement therapy (RRT). In patients requiring RRT for more than two weeks or those who develop ESKD, tunneled hemodialysis catheter (HDC) insertion is preferred, based on a lower risk for infectious complications. While the efficacy of ultrasound (US)-guided tip positioning in antegrade-tunneled HDCs has previously been shown, its application for the insertion of retrograde-tunneled HDCs has not been described yet. This is especially important, since the retrograde-tunneled technique has several advantages over the antegrade-tunneled HDC insertion technique. Therefore, we here report our first experience of applying the rapid atrial swirl sign (RASS) for US-guided tip positioning of retrograde-tunneled HDCs. Methods: We performed a cross-sectional study to assess the feasibility of applying the RASS for US-guided tip positioning of retrograde-tunneled HDCs. We performed a total number of 24 retrograde-tunneled HDC insertions in 23 patients (requiring placement of a HDC for the temporary or permanent treatment of ESKD) admitted to our Department of Nephrology and Rheumatology at the University Medical Center Göttingen, Germany. Results: The overall success rate of applying the RASS for US-guided tip positioning of retrograde-tunneled HDCs was 24/24 (100%), with proper tip position in the right atrium in 18/23 (78.3%), or cavoatrial junction in 5/23 (21.7%) when RASS was positive and improper position when RASS was negative in 1/1 (100%), confirmed by portable anterior-posterior chest radiography, with only minor post-procedural bleeding in 2/24 (8.3%). In addition, this insertion technique allows optimal HDC flow, without any observed malfunction. Conclusion: This is the first study to investigate the efficacy of the RASS for US-guided tip positioning of retrograde-tunneled HDCs in patients with ESKD. Application of the RASS for US-guided tip positioning is an accurate and safe procedure for the proper placement of retrograde-tunneled HDCs.