For you to be eligible for the longer, five-year plan, your income must exceed the median income for your state for a family of your size. Depending on the size of your debts and available income, this may lower your payments – your debts are divided into 60 installments rather than 36 – but the downside is that your financial life will be governed by the court for a longer period of time. For example, you can't take on any new debt during your Chapter 13 plan without special permission from the court.
If your income is less than the median income for your state and your family size, you qualify for a three-year plan. If you would prefer a longer time, you can request an extension from the court, but you'll have to present the judge with a good reason. Generally, simply wanting to lower your payments isn't enough.
When Payments Start
Your first payment is due within 30 days after you file for bankruptcy, even if your Chapter 13 plan hasn't yet been approved by the court. The trustee will hold your money until your plan is confirmed, and then she will turn it over to your creditors.