A whole chicken can keep up to a year in the freezer. Frozen chicken parts can last up to 9 months. But that will depend on how good the freezer is at maintaining temperature and how well the chicken is packaged for freezing. Make sure the chicken is packed securely and air-tight. Use packaging designed for freezing. Any air pockets or loose packaging will allow the food to dry out or become freezer-burned.
Freezing preserves food forever since it stops growth of bacteria. The problem is the quality of the taste diminishes with time. It should be good up to six months if it doesn't get freezer burnt by then.
Just so you know - once chicken has been frozen below 26°F, it can no longer be called 'fresh'.