Purpose: Newcomer dyslexic children face a double disadvantage: They must catch up on the schooling delay caused by their late arrival in France, while the lack of early diagnostic tools for dyslexia delays their access to appropriate intervention. However, cognitive predictors of decoding skills in alphabetic scripts are well known. Clinicians and teachers could use the latter for early identification of children at risk of reading disorders. This study aimed to determine whether the main cognitive predictors of decoding skills in monolingual children efficiently predict reading skills in newcomer children. We also compared the performance of both groups on these predictors. Method: A total of 165 monolingual and 157 newcomer primary school children completed tasks assessing decoding skills, phonological awareness, rapid automatized naming, nonword repetition, vocabulary, and visual-verbal paired-associate learning. Results: Cognitive predictors showed a strong correlation with decoding abilities in newcomer children. However, the latter scored lower than monolingual children on all predictors except for nonword repetition, probably thanks to its universal properties. Conclusions: Cognitive predictors can be used to identify newcomer children at risk of reading failure, provided that specific norms and tests are developed, except for the nonword repetition task. Native norms should be used for newcomers on this task, as monolingual and newcomer children showed similar performance. We also provide recommendations to establish norms for the other tests.