The EFSA Panel on Plant Health performed a pest categorisation of Nipaecoccus viridis (Hemiptera: Sternorrhyncha: Pseudococcidae), the spherical scale, for the EU. It is of Asian origin and occurs widely in southern Asia, Africa and tropical Australia. It has been introduced to a few countries in the Americas. In the Mediterranean basin it is found in Algeria, Egypt, Israel, Syria and Turkey, where it is limited to the Marmara region. It has not been reported within the EU. It is not listed in Annex II of Commission Implementing Regulation (EU) 2019/2072. It reproduces sexually, has three generations each year in citrus orchards in South Africa, and all stages can overwinter. First instar nymphs may move to neighbouring plants by crawling or be passively dispersed by wind or hitchhiking on clothing, equipment or animals. It is highly polyphagous, feeding on plants in 115 genera and 46 families. It is an important pest of citrus (Citrus spp.), cotton (Gossypium spp.), mango (Mangifera indica), avocado (Persea americana) and stored potatoes (Solanum tuberosum). It also feeds on a wide range of other fruit (apple Malus domestica, olive Olea europea, pear Pyrus communis and grape Vitis vinifera) and vegetable crops (tomato Solanum lycopersicum), and ornamental plants (roses, Rosa spp.) that are widely grown in the EU. Plants for planting, fruits, vegetables, and cut flowers are the main potential pathways for entry of N. viridis into the EU. Climatic conditions and availability of host plants in southern parts of the EU where there are few days of frost each year would likely allow this species to successfully establish and spread. Reductions in yield and quality of cultivated hosts including avocado, citrus, cotton and mango is anticipated if establishment occurs. Phytosanitary measures are available to reduce the likelihood of entry and spread. N. viridis meets the criteria that are within the remit of EFSA to assess for this species to be regarded as a potential Union quarantine pest.