From the WSJ via the SMH:
October 17: US will exhaust emergency measures. Expect to only have $US30 billion in cash and incoming tax revenue to pay obligations
October 22: First day the US could start missing payments
October 23: $US12 billion in Social Security payments due
October 24: Rollover of at least $US93 billion in maturing debt. Will investors expect higher yield?
October 28: $US3 billion in federal employees’ salaries to be paid
October 30: Medicaid providers to be paid $US2 billion
October 31: $US6 billion interest payments due and a rollover of at least $89 billion in maturing debt
November 1: $US55 billion in Medicare, Social Security and military payments due