Only individuals with "regular income" may be debtors under Chapter 13. 11 USCA § 109(e).
An "individual with regular income" is an individual "whose income is sufficiently stable and regular to enable such individual to make payments under a plan under Chapter 13 . . ." 11 USCA § 101(30).
You don't have to have any "disposable" income, beyond that necessary to pay for your allowed expenses. You could file a 0% plan and pay nothing to your creditors during the plan. This is a rare outcome, because most such debtors will file Chapter 7. But, it's legally possible.
Hope this helps.
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