Obama signed the bills during a weekend golf vacation in Southern California.
The debt limit measure allows the government to borrow money to pay its bills, such as Social Security benefits and federal salaries. Failure to pass the measure, which the Senate passed 67-31 earlier this week and sent to Obama for his signature, most likely would have sent the stock market into a nosedive.
The Treasury Department is now free to borrow regularly through March 15, 2015, meaning lawmakers won't have to revisit the issue until a new Congress is sworn in after the November elections.
Separate legislation passed in December would have held annual cost-of-living increases for veterans age 62 and younger to 1 percentage point below the rate of inflation, beginning in 2015. The measure was designed to hold the line on the soaring cost of government benefit programs, which have largely escaped trillions of dollars in deficit cuts over the past three years.
The cuts were enacted less than two months ago, with a projected savings to the government of $7 billion over a decade. Veterans groups and some lawmakers said the cut was a mistake, and they began campaigning to have the benefits restored.
The pensions go to veterans who retire after 20 years of service, regardless of their age. Nearly 2 million retirees currently are eligible, including about 840,000 under age 62, according to the Pentagon.
For a sergeant first class who leaves the service at age 42 after two decades, the bill passed in December would have meant an estimated $72,000 in reduced pension payments.
Quick action by lawmakers on this year's debt limit bill stands in contrast to lengthy showdowns in 2012 and last fall, when Republicans sought to use the must-pass bill as leverage to win concessions from Obama. They succeeded in 2011, winning about $2 trillion in spending cuts. But Obama has been unwilling to negotiate over the debt limit since his re-election in 2012.
The bill he signed Saturday is the third consecutive debt measure to pass Congress without concessions from the White House.
Republicans also have been less confrontational since a 16-day partial government shutdown last October sent the party's poll numbers skidding.
Both bills were flown out to Obama in California late Friday night, a White House aide said.