Understanding genomic characteristics of non-model organisms can help bridge gaps in ecology and evolutionary sciences, but lack of a reference genome and transcriptome for these species challenges their study. We advance this goal by conducting the first full genome and transcriptome sequence assembly and analysis of the non-model organism Kellet’s whelk, Kelletia kelletii, a marine gastropod and fisheries species exhibiting a northern range expansion along the US west coast that is potentially driven by climate change. We used a combination of Oxford Nanopore Technologies, PacBio, and Illumina platforms for sequencing, and integrated a set of bioinformatic pipelines to create a comprehensive and contiguous de novo genome assembly. Our results represent the most complete and continuous documented genome among the Buccinoidea superfamily to date. Genome validation revealed its relatively high completeness with low missing metazoan BUSCOs, and an average coverage of ~70x for all contigs, indicating a robust assembly. Characteristics of the K. kelletii genome showed that short-read data contributed significantly to genome coverage and accuracy; however, long-read data was imperative to the completeness and continuity of the genome assembly. Genome annotation identified a large number of protein-coding genes compared to other closely related species, suggesting the presence of a complex genome structure. We conducted the transcriptome assembly and analysis of individuals during their period of peak embryonic development, and revealed highly expressed genes associated with specific GO terms and metabolic pathways, most notably lipid, carbohydrate, glycan, and phospholipid metabolism. We also identified numerous heat shock proteins (HSPs) in the transcriptome and genome with a potential association between the transcriptional expansion of HSP families and the marine environment experienced by the sessile life history stage of the developing embryo. This study offers a valuable reference genome and transcriptome for conducting comprehensive bioinformatic analyses of the non-model organism K. kelletii. Such resources will enhance our understanding of its ecology and evolution, as well as that of other coastal marine species facing environmental changes.