As a general rule, there is no statutory prohibition against an individual filing another bankruptcy at any time. However, the court could enter such an order (for example if you are found to be abusing the system by repeatedly filing cases solely for purposes of delay). Additionally, the Bankruptcy Code [11 USC §109(g)] does provide that you may have to wait 180 days (6 months) to refile if either: (a) your previous case was dismissed for willful failure to abide by orders of the court (possible examples could include the failure to pay filing fees, to file required documents, or to complete the first meeting of creditors), or (b) if your case was dismissed on your request after a creditor filed a motion for relief from the automatic stay. In addition, there are certain prohibitions against receiving another chapter 7 discharge in specific circumstances. See 11 USC §727(8) and (9).
Subsection (8) prohibits entry of a chapter 7 discharge if you received a discharge in a chapter 7 or 11 case filed within eight (8) years of the filing of the new case.
Subsection (9) prohibits entry of a chapter 7 discharge if you received a discharge in a chapter 12 or 13 case commenced within six years of the chapter 7 filing unless payments under the plan totaled either 100% of allowed unsecured claims or at least 70% of the unsecured claims if the plan was proposed in good faith and was the debtor's best effort.
Moreover, under 11 USC §1328(f)(1) and (2), a discharge cannot be entered in a chapter 13 case if the debtor (1) has received a discharge in a chapter 7, 11, or 12 case filed within four years of the chapter 13 filing, or (2) has received a discharge in a chapter 13 case filed within 2 years of the new chapter 13 case.
For other things that should be considered before actually filing another bankruptcy petition, see Who Can Start a Bankruptcy? and What are the Consequences of Filing for Bankruptcy?
Only an individual may file a Chapter 13 petition. As with Chapter 12 cases, there are debt limitations in a Chapter 13 case. See 11 USC §109(e).