Successive UK government policies have strengthened the phonics element of the National Curriculum for English in England. The policies have included inviting publishers to submit completed self-assessments of their systematic phonics programmes. The self-assessment criteria focus on what is deemed to be 'high-quality provision', as defined in the "Independent Review of the Teaching of Early Reading" chaired by Jim Rose. The programmes whose self-assessments were judged to be accurate by small panels of independent evaluators have been subsequently listed on a central government website. The authors have acted as independent evaluators in this process and, between them, had the opportunity to inspect the content of over 100 phonics programmes. They have noted that many of these programmes (most of which did not meet the Rose criteria) contained numerous linguistic inaccuracies, particularly in relation to the English spelling system and its grapheme-phoneme correspondences. The existence, number and range of these errors jeopardise policy implementation and National Curriculum delivery and pose risks for the quality of teaching and learning. The article suggests some reasons for these findings in related published debates and in policy documents, and that phonics programmes need to be more linguistically-informed. The article concludes with some implications for practice.