Purpose: We assessed the treatment outcome and the benefits of routine follow-up visits in T1 glottic laryngeal squamous cell carcinoma (LSCC). Methods: Medical records of patients diagnosed with stage T1 glottic LSCC (N = 303) in five Finnish university hospitals between 2003 and 2015 were reviewed. Moreover, data from the Finnish Cancer Registry and the Population Register Center were collected. Results: Of all 38 recurrences, 26 (68%) were detected during a routine follow-up visit, and over half (21 of 38, 55%) presented without new symptoms. Primary treatment method (surgery vs. radiotherapy) was not connected with 5-year disease-specific survival (DSS) or laryngeal preservation rate. Conclusion: The majority of recurrences were detected on a routine follow-up visit, and local recurrences often presented without new symptoms. Routine post-treatment follow-up of T1 glottic LSCC seems beneficial. Trial registration: Trial registration number and date of registration HUS/356/2017 11.12.2017. [ABSTRACT FROM AUTHOR]