We present a genome assembly from an individual Gibbula magus (the turban top shell; Mollusca; Gastropoda; Trochida; Trochidae). The genome sequence is 1,470 megabases in span. Most of the assembly is scaffolded into 18 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 16.1 kilobases in length. Gene annotation of this assembly on Ensembl identified 41,167 protein coding genes.