Retirement Plan Tax Rules, Part 2

A KEOGH retirement plan can be set up by self-employed individuals and does not require advanced IRS approval. There are two types of KEOGH plans available. One is defined-benefit, which allows participants to contribute a maximum of the lesser of either 100 percent of their average compensation for the three consecutive years of highest compensation as an active participant, or $160,000. Then there's defined contribution, which allows for contributions of up to $40,000 for either a profit-sharing defined contribution plan or a money-purchase plan. The deadline for setting up a KEOGH plan is the end of the tax year (December 31), and the deadline for making contributions to the KEOGH plan is the same as the SEP--the due date for your Form 1040 individual tax return (including extensions).

Source: "Selecting the Right Retirement Plan"