Spanish phonemes and the Spanish orthography

The Spanish writing system or orthography is noteworthy for the transparent relation between the letters of the alphabet and the phonemes of Spanish, although this does assume a Castilian model of pronunciation as opposed to, say, an Andalusian one or a Chilean one.

The table below shows the letter or letters of the alphabet that correspond to each of the Spanish phonemes.

Note that a capital letter between slashes denotes an archiphoneme, which occurs in contexts of neutralization. In such cases, Spanish uses the letter r for vibrants (i.e. /R/) and the letter l for laterals (i.e. /L/); among the nasals (i.e. /N/), it uses m for bilabials and n in the remaining cases. This latter circumstance explains why words like Enrique, tengo, ancho and confuso all have n as their nasal despite the fact that in each case the precise sound is different, viz. [n], [ŋ], [ɲ] and [ɱ].

Phoneme–letter correspondence in Spanish
/a/ a /ʝ/ y
/e/ e // ch
/i/ i, -y /x/ j; g (before i or e)
/o/ o /m/ m
/u/ u /n/ n
/p/ p /ɲ/ ñ
/t/ t /N/ n; m (before bilabial cons.)
/k/ c; qu (before i or e) /l/ l
/b/ b, v /ʎ/ ll
/d/ d /L/ l
/g/ g; gu (before i or e) /ɾ/ r
/f/ f /r/ rr
/θ/ z; c (before i or e) /R/ r
/s/ s    

The letter h is silent in all cases and so corresponds to no phoneme.

The letter x corresponds in principle to the sequence /ks/, as in [ˈeksito] éxito ‘success’. When this sequence forms a cluster with a following consonant, there is a tendency for /k/ to be weakened or elided, as in [estɾaŋˈxeɾo] ‘foreign’. This is a variable process, however, and [ekstɾaŋˈxeɾo] would also be possible, particularly in more careful speech.