The nation's $16.4 trillion borrowing limit was temporarily suspended by Congress in February, and will be reimposed on May 19. At that point, the ceiling will be automatically hiked to cover whatever borrowing occurred during the suspension period — the government currently has $16.8 trillion in public debt outstanding.
At that point, the Treasury would begin to employ its "extraordinary measures," to free up funds and keep the nation current with its obligations. The question now is how much time those measures will buy Congress and the White House to hammer out a deal to raise the limit.
The Bipartisan Policy Center, which closely tracks the nation's debt limit, estimated in April that the debt-limit fight could stretch into as late as October without a default, depending on exactly how the nation's finances shake out.