You can vary the profit sharing percentage from 25% of your salary or earnings to all the way down to zero%. It works the same with the 401k salary or earnings deferral. You can have a maximum 401k deferral of $17,500 in 2014 ($23,000 age 50) or all the way down to a zero deferral.The profit sharing feature of your retirement plan allows you to make an additional contribution of up to 25% of your salary or earnings.The total amount of both the 401k deferrals and the profit sharing contributions are limited to a maximum of $52,000 in 2014. The maximum amount for 2015 is increased to $53,000.ou can vary the profit sharing percentage from 25% of your salary or earnings to all the way down to zero%. It works the same with the 401k salary or earnings deferral. You can have a maximum 401k deferral of $17,500 in 2014 ($23,000 age 50) or all the way down to a zero deferral.