For decades, researchers have debated whether readers benefit from translating visual word forms into phonological codes. A focus of this debate has been on the earliest moments of processing when a word is perceived in parafoveal vision (i.e., phonological preview benefit). A recent meta-analysis (Vasilev et al., 2019) concluded that the phonological preview benefit may be small and unreliable but they did not take into account potentially important stimulus-level or participant-level factors that varied across the included studies. Therefore, we conducted two well-powered experiments that systematically investigated the effects of sentence constraint, preview lexicality, and participant language skills on the phonological preview benefit effect. We found phonological preview benefits that were larger in high versus low constraint sentences, larger for words than pseudowords, and larger for better spellers. We conclude that phonological codes do facilitate early word recognition during reading, but that the phonological preview benefit magnitude depends on subject- and stimulus-level factors.