There are currently no studies that examine the types of phonemic awareness errors children are making on tests of phonemic awareness. This study aimed to: (a) develop a taxonomy to categorize the different types of errors made on a test of phoneme segmentation by grade one children, (b) determine which error categories and error types occur most frequently, and (c) determine which types of words were the most difficult to segment. We examined errors made by 215 children on a test of phoneme segmentation, and developed a taxonomy for classifying the different categories and types of errors observed. The most frequently occurring category of errors was Addition errors, specifically the addition of a schwa vowel to a phoneme in the word. Additionally, children made more errors on test items that contained consonant blends. Knowledge of the different types of phonemic awareness errors children make will be valuable for teachers and speech-language pathologists when providing phonemic awareness instruction or intervention. Further research in this area is required to determine how meaningful different types of phonemic segmentation errors are in relation to overall phonemic awareness abilities and reading abilities.