A new and distinct grapevine variety ‘Sugrafortyfive’ is characterized by the production of a medium-sized, dark berry with near black skin color and an ellipsoidal, elongated shape. The berries of ‘Sugrafortyfive’ ripen early and are firm and very juicy. The new variety ‘Sugrafortyfive’ has a similar harvest time as ‘Summer Royal’ (unpatented) but the shape of the berry of the new variety ‘Sugrafortyfive’ is ellipsoidal elongated compared to round for ‘Summer Royal’.