In orthographies studied to date, children learning to spell tend to omit one consonant of a cluster—for initial clusters, the second consonant, and for medial nasal clusters, the nasal. Explanations have included a special status for the initial consonant of a word, and the fact that in English nasal clusters are not true clusters but consist of a nasalised vowel plus a consonant. We tested children’s spelling of initial and medial clusters consisting of a nasal consonant followed by another consonant, but non-nasalised vowels, in Kiswahili. For both initial and medial clusters, the nasal was spelled wrongly more often than the other consonant. The initial position in a word does not seem to have special properties. Rather, the spelling of clusters seems to depend on the properties of the individual phonemes, nasals being particularly difficult to spell. It is concluded that cross-linguistic studies of spelling development are necessary to draw generalised conclusions about phonological processing.