Of the syllabic nasals, the most frequently found and the most important is n. When should it be pronounced? A general rule could be made that weak syllables which are phonologically composed of a plosive or fricative consonant plus an are uncommon except in initial position in the words. So we can find words like 'tonight' tənaɪt, 'canary' kəneəri, 'fanatic' fənætɪk, 'sonata' sənɑ:tə with a before n, but medially and finally - as in words like 'threaten', 'threatening' - we find much more commonly a syllabic n: θretṇ, θretṇɪŋ. To pronounce a vowel before the nasal consonant would sound strange (or at best over-careful) in the BBC accent.

Syllabic n is most common after alveolar plosives and fricatives; in the case of t, d, s, z followed by n the plosive is nasally released by lowering the soft palate, so that in the word 'eaten' i:tn, for example, the tongue does not move in the tn sequence but the soft palate is lowered at the end of t so that compressed air escapes through the nose. We do not usually find n after l,  ʧ ,  ʤ, so that for example 'sullen' must be pronounced ʃΛlən, 'Christian' as krɪstʃən (though this word may be pronounced with t followed by i or j) and 'pigeon' as pɪʤən.

Syllabic n after non-alveolar consonants is not so widespread. In words where the syllable following a velar consonant is spelt 'an' or 'on' (e.g. 'toboggan', 'wagon') it is rarely heard, the more usual pronunciation being təbɒgən, wægən. After bilabial consonants, in words like 'happen', 'happening', 'ribbon' we can consider it equally acceptable to pronounce them with syllabic n (hæpn, haepṇɪŋ, rɪbn) or with ən (hæpən, hæpənɪŋ, rɪbən). In a similar way, after velar consonants in words like 'thicken', 'waken', syllabic n is possible but an is also acceptable.

After f, v, syllabic n is more common than an (except, as with the other cases described, in word-initial syllables). Thus 'seven', 'heaven', 'often' are more usually sevn, hevṇ, ɒfṇ= than sevən, hevən, ɒfən.

In all the examples given so far the syllabic n has been following another consonant; sometimes it is possible for another consonant to precede that consonant, but in this case a syllabic consonant is less likely to occur. If n is preceded by l and a plosive, as in 'Wilton', the pronunciation wɪltən= is possible, but wɪltən is also found regularly. If s precedes, as in 'Boston', a final syllabic nasal is less frequent, while clusters formed by nasal + plosive + syllabic nasal are very unusual: thus 'Minton', 'lantern', 'London', 'abandon' will normally have a in the last syllable and be pronounced mɪntən, læntən, lΛndən, əbændən. Other nasals also discourage a following plosive plus syllabic nasal, so that for example 'Camden' is normally pronounced kaemdən.