$24,500 is your maximum employee elective deferral. The $14,473 is the maximum employer contribution, 20% of your net profit minus the deductible portion of your self-employment taxes. Assuming that you have no other employment that would put you over the Social Security wage limit, the $14,473 maximum employer contribution implies that your net profit from self-employment is about $80,555. The calculations are shown on TurboTax's Keogh, SEP and SIMPLE Contribution Worksheet.
When you contribute to an individual 401(k), you designate the amount that is employee elective deferral ($24,500) and the amount that is employer contribution ($14,473). The contribution form used by your 401(k) trustee is likely to have separate entries for each of these amounts.
