Many low-skill readers have problems with visual word recognition. In particular, low-skill readers show a substantial nonword reading deficit that is attributed to deficits in sub-lexical processing. In this study, I examined whether the nonword deficits of German 14-year-old low-skill readers were associated with inefficient use of multi-letter information. In a lexical-decision experiment, words and nonwords were presented in standard format and in MiXeD cAsE format which has been shown to be especially disrupting for sub-lexical processing. When the stimuli were presented in standard format, low-skill readers showed a substantial nonword reading deficit, that is they were generally slower than high-skill readers, but had special problems with decoding nonwords. However, when stimuli were presented in MiXeD cAsE, low- and high-skill readers showed equal impairments in nonword processing. This finding indicates that low-skill readers do not use context-sensitive multi-letter rules during phonological assembly in normal reading. (Contains 2 tables.)