Background <p>Morphological identification of phlebotomine sand flies in Belize has historically relied on greyscale illustrations and taxonomic keys, which can limit identification accuracy and accessibility for non-specialists. Building on our recent investigation of the spatiotemporal distribution of sand flies in the country, we provide a coloured pictorial guide to the species collected.</p> Methods <p>Sand flies were collected in north-west and central east Belize between 2023 and 2025 and identified morphologically using established taxonomic keys. Representative voucher specimens were deposited in the Coleção de Flebotomíneos (FIOCRUZ/COLFLEB), Belo Horizonte, Brazil.</p> Results <p>We present 65 coloured photomicrographs covering 20 species, including 18 previously reported in Belize and two species (<i>Lutzomyia longipalpis</i> and <i>Psathyromyia soccula</i>) recorded in the country for the first time. The guide highlights key diagnostic characters, including male genitalia, spermathecae, cibarium, and other external morphological features, and integrates both coloured and greyscale images. A dichotomous key to the collected species is also provided.</p> Conclusions <p>This pictorial guide complements existing taxonomic resources and aims to improve consistency and accessibility of sand fly identification in Belize. The integration of coloured photomicrographs with conventional morphological keys provides a practical resource to support vector surveillance and future taxonomic work.</p> Graphical Abstract <p></p>