In 2021, a series of radiocarbon dates for St. George’s Rotunda in Nitrianska Blatnica (Slovakia) was published. The samples were acquired during restoration work. Based on the analysis, the authors dated the rotunda to the period of around AD 820–887, with 86% of the probability distribution lying in the period before AD 863. The chronology is based on the combined radiocarbon date 1191 ± 10 BP, which was obtained from four samples of wood fragments found in the oldest mortar layer. However, the date proposed by the authors raises concerns. The conclusions were based on a selection of samples and modeling of radiocarbon dates but put less emphasis on the results of many years of broad archaeological research on the local settlement agglomeration as well as extant historical and archaeological knowledge. The present re-analysis of the early medieval mortar and plaster samples and simple modeling corroborates the alternative hypothesis, providing us with the date 1115 ± 13 BP (cal AD 892–988 2σ). The resulting probability range is consistent with current archaeological and historical knowledge. Consequently, contrary to former conclusions, the construction of the rotunda should be dated to the period between the end of the 9th century and the end of the 10th century.