Boron accumulates in plants with the same isotopic ratio as found in the source soil and water, producing isotope ratios (¹¹B/¹⁰B) that reflect those of the sources, thus indicating the provenance of products derived from vegetative matter. We developed and validated a simple analytical method based on gas collision inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) for the determination of B isotope ratios to distinguish the geographic origins of wines. Use of the gas collision technique (using Ne as the collision gas) in ICP-QMS can effectively improve the precision and accuracy of ¹¹B/¹⁰B determination, which may be due to improvement of the ion transmission or sensitivity (via collisional focusing) and a reduction in plasma noise (via collisional energy damping). Compared with the conventional method (without Ne gas collision), the precision of the ¹¹B/¹⁰B ratio was improved 3.2-fold (from 3.15‰ to 0.94‰) and the accuracy was improved from an error of −5.5% to −0.1%. The −0.1% error represents mass bias, resulting from in-cell gas collision, and can be accurately corrected using an external bracketing technique with NIST SRM-951 B isotope standard. Direct dilution of the wines by a factor of 100 with 1% HNO₃ was found to substantially reduce matrix-induced mass discrimination. Other important parameters such as detector dead time, dwell time per data acquisition, and total integration time per isotope were also optimised. Twenty wines from nine countries were analysed, and δ¹¹B values ranged from +1.73 to +46.6‰ with an average external precision (N = 5) of 0.82–1.63‰. The proposed method has sufficient precision to distinguish between 20 wine brands originating from four different geographic regions.