District Judge Horace Ward provided what could prove to be a short-lived reprieve for the 31- year-old so that he could have more time to study the case.
But prison officials said that the execution had been re-scheduled for midnight tonight, British time.
Earlier, the battle to save Ingram had seemed irrevocably lost, as Georgia's Pardons and Paroles Board rejected his appeal for clemency, and grim preparations had entered the final death watch phase. His head and leg had been shaved as the first stage of the journey to the electric chair.
Less than four hours before the stay, Ingram had bade last farewells to his parents and family. Prison officials told reporters that he had been in "angry and irritable" mood. When asked whether he wanted to make a last statement, and told it would be taped, he replied: "I don't have anything to say to you or that tape recorder."
Judge Ward seems to have ordered the stay to study the issue brought up by the defence, that Cambridge-born Ingram was so drugged by the Georgia state authorities with the tranquiliser Thorazine during his 1983 trial that he could not help his attorneys defend him.
Before the reprieve was announced, his mother, Ann, said as she left the prison, having visited her son for what she thought had been the last time: "I couldn't believe how brave he was, he wasn't crying. We're the ones who are breaking up.
"How do you think it feels to see your son for the last time, hug him and kiss him, and know you'll be making his funeral arrangements a few hours from now?" she added, choking back tears.
Nine hours earlier, Ingram's hopes appeared dashed when the state's Pardons and Paroles Board unanimously turned down his appeal for clemency.
A sombre Wayne Garner, the board's chairman who, along with his four colleagues, held Ingram's life in his hands, said: "Our unanimous opinion was the punishment fits the crime."
Echoing the overwhelming support for the death penalty across the US, the silver-haired Mr Garner said in his southern drawl that "there are crimes so violent, so heinous, that it [capital punishment] is proper".
In reaching its "very difficult" decision, he left no doubt that the board's discussions with the victim's relatives had weighed more heavily than the pleas for mercy from Ingram's own family at Wednesday's hearings - and his unprecedented 20-minute face-to-face meeting with Ingram that evening in his 9ft by 6ft cell at the macabrely named Georgia Diagnostic and Classification Center, 40 miles south of Atlanta.
Ingram's is the first capital case since Mr Garner became the board's chairman. "We don't parole life sentences without one member of the board interviewing them," he said later. "How can I make a decision to execute a man without at least looking him in the eye?"
David Marshall, of the British Bar's Human Rights Committee, who is helping with the defence here, described Ingram as in "a state of terror".
All that, however, counted less than the views of Mary Sawyer, wounded when Ingram, during a drunken crime binge, shot and killed her husband, JC Sawyer, on 3 June, 1983. Five months later, on his 20th birthday, he was condemned to die.
Earlier, Ingram exchanged last farewells with his family according to a carefully organised schedule - first with aunts and brothers, and then with his sister, and finally with his American father, Johnny, and his mother. He was also seen by a "non-Christian spiritual adviser".
Even before the Pardons Board delivered its expected judgment, Ingram's main lawyer, Clive Stafford Smith, had started the ritual "judge-hunt", hoping for a sympathetic judge to issue a stay, so that new evidence could be brought. First on the list for his faxed appeals was the Georgia Supreme Court, which rejected lawyers' pleas. But then they went to the federal district court which granted the stay of execution.
Fifty-three Labour MPs, the President of the European Parliament, hundreds of ordinary people around the world and the Archbishop of Canterbury had appealed for clemency.
But outside Georgia the affair has gone virtually unnoticed in the US, apart from Ann Ingram's vain appeal to John Major to intercede. This reflects the strong support for the death penalty in America. In Georgia that support runs at 90 per cent.