São Toméan Portuguese (Portuguese: Português Santomense or Português de São Tomé) is a dialect of Portuguese spoken in São Tomé and Príncipe.
It contains many archaic features in pronunciation, vocabulary, grammar, and syntax, similar to Brazilian Portuguese. It was once the dialect of the owners of the roças and the middle class, but now it is the dialect of the lower and middle classes, as the upper class often uses modern European Portuguese standard pronunciation, which is now also used by lower and middle classes.
São Tomé is the third country in order of percentage of Portuguese speakers (after Portugal and Brazil), with more than 95% of the population speaking Portuguese, and more than 50% using it as their first language. The rest of the population speak Portuguese creoles.