Quite simply, annual salary generally refers to the annual amount of money employees are paid for their work, and what other times might be called base pay. It doesn’t usually include variable pay or non-monetary types of compensation.
Annual compensation, on the other hand, is the base salary added to the value of variable pay like bonuses and commissions, as well as non-monetary types of compensation, which might also be referred to as benefits or perks. Those could include health insurance, a dental plan, a 401(k) (or other retirement plans), equity, paid vacation time, tuition assistance, childcare, discounted parking, gym memberships and more.