Higgs was quickly escorted to a waiting car by five deputies and his attorney.
"He's very happy to be free," said lawyer, David Houston, who refused other comment outside the Washoe County Jail in Reno.
Higgs, wearing jeans and a sweat shirt and carrying a plastic bag with what appeared to be his personal belongings, did not say much.
Asked what he planned to do first, Higgs said, "Hug my mom."
Another of Higgs' lawyers, Alan Baum of Woodland Hills, Calif., had said Higgs' family was putting up property to cover his $250,000 bail.
Higgs' mother plans to relocate from North Carolina to the Reno area to support him before his scheduled trial in June, Baum said.
Higgs, who has pleaded not guilty to murder charges, will remain in the Reno area, Baum said.
Washoe County District Judge Steven Kosach on March 1 set bail, with provisions that Higgs remain in daily contact with his lawyers and not leave the state. Higgs had been held without bail.
Augustine's family sharply criticized Kosach's order setting bail, calling Higgs a "psychopath" who should remain in jail.
Higgs, an emergency room nurse, is accused of poisoning Augustine with a fatal injection of succinylcholine, a drug used to temporarily paralyze a person before inserting a breathing tube.
Doctors initially believed Augustine suffered a massive heart attack before she was taken to the hospital July 8. She lapsed into a comma and died three days later.
Acting on a tip, doctors took samples from Augustine before her death that were later tested by the FBI toxicology lab.
Higgs attempted suicide in Las Vegas three days after Augustine's death. He was released from a hospital the same day and didn't attend his wife's funeral.
He was arrested Sept. 29 in the driveway of his brother's home in Hampton, Va., after toxicology tests were complete.
Authorities also are investigating whether foul play was involved in the death of Augustine's former husband, Charles Augustine, 63, who was under Higgs' care when he died in Las Vegas in 2003.
Authorities exhumed his body after Higgs' arrest. Kathy Augustine and Higgs were married three weeks after Charles Augustine died.