The Intention for Fasting

Q: Saum-35: Can the intention for fasting be made in one's mother tongue (such as English or Gujarati)?

Answer: It is not necessary to verbally state the intention for fasting. Merely having the intention in the heart is sufficient. It is however best and not at all forbidden to verbally state the intention, which may be in Arabic or in one?s mother tongue.

Fatawa Rahimiyyah vol.3