Savings Incentive Match Plan for Employees, or SIMPLE is available in both IRA and 401(k) formats. SIMPLE IRAs are the most common, and are great as a starter plan for small businesses. But eventually the limitations of a SIMPLE will wear on an employer, so they may consider making the change to 401(k). October is the best time to consider converting a SIMPLE to a 401(k). SIMPLE notices are required to be delivered by November 2, so a decision must be made prior to that for the upcoming year. Learn more below about the differences between a SIMPLE vs 401k, and choose 401(k) today, before your chance for this year passes.