Vesting refers to the ownership of your retirement account assets. When you make a salary deferral contribution to your account assets, the money is 100% yours. When your Employer makes a contribution or matches your contribution, your ownership of those funds may be vested over time as specified in the Summary Plan Description. A common vesting schedule for retirement accounts is the graded vesting schedule where your ownership of Employer contributions in your account increases gradually over several years until they become fully vested. For example, in a five-year graded vesting schedule, you are 20% vested after the first year, with the percentage of ownership increasing in 20% increments each subsequent year until you reach full vesting by year 5.