Is SnF3 ionic or covalent

Answer 1

This could be two different entities.

Snf3 is a protein involved in the control of glucose uptake in yeast. Proteins are basically covalently bound, though other types of bonding are involved in their secondary and tertiary structures.

SnF(subscript 3)(superscript -) is an ion, not a complete compound. Its internal bonding is covalent.

Answer 2

SnF3 is likely to be covalent. Fluorine is a highly electronegative atom and tends to form covalent bonds with other elements. Tin (Sn) is a metal, but in this case, because of the electronegativity difference between tin and fluorine, it is more likely that covalent bonds are formed in SnF3.