Hunter, 76, admitted suffocating Janice, his wife of 52 years, at their home on the island, after she “begged him” to end her life as she suffered from blood cancer.
Judges at Paphos District Court imposed a two-year jail sentence on Hunter, who has already spent 19 months in custody.
His legal team said he had been released shortly after the sentencing when Cypriot prison authorities had officially calculated his release date.
Judges previously found Hunter not guilty of the more serious charge of premeditated murder.
Mr Hunter, fron Ashington, Northumberland, said he “can’t describe” how he was feeling as he appeared outside court in Cyprus for the first time since being released from custody, and thanked everyone who donated to the fundraising appeal for his legal costs.
Speaking on the steps of Paphos District Court, a visibly emotional Mr Hunter said: “I’d like to say thank you to all the people who’ve donated to me, and especially my mates and my workmates. I don’t know where I would be without them.”
The former miner added: “When you work in a colliery, you’re a family.”
Asked how he was feeling, Mr Hunter said: “I can’t describe it. I’m sorry. I wish I could, I wish I could find words to describe it but I can’t.
“When you’re under pressure for two years, not knowing which way it’s going to go.”
Read more: Expat who killed his terminally-ill wife now due to be sentenced next week
Mr Hunter’s daughter Lesley Cawthorne said: “I’m elated and relieved that my darling dad has been released. The past 19 months have been a living nightmare for our family but today is the start of us being able to rebuild our lives.
“Dad’s release also means we can finally grieve for my mum and I hope everyone can respect our privacy whilst we take the time to come to terns with her loss.
“So many people have worked hard and supported our efforts to bring my dad home, too many to mention but you know who you are and you know you have our deepest gratitude.
“The kindness and love of friends and strangers has been the thing that has kept us going and we can never thank you all enough.”
Read more: Expat whose wife ‘begged him’ to kill her found guilty of manslaughter in Cyprus
Michael Polak, of Justice Abroad, which has been representing David Hunter, said: “We are very pleased with the sentence today which means that David will be free immediately.
“The sentencing exercise was not a simple one given that a case like this has never come before the courts of Cyprus before.
“We submitted extensive sentencing case law from across the common law world, from Australia to Canada, New Zealand, and the United Kingdom to assist the court in coming to a decision which was fair.
“The result of today’s hearing, and the court’s previous decision finding Mr Hunter not guilty of murder, is what we have been fighting for in this case, and David is very pleased with the outcome today.
“This has been a tragic case and difficult for all of those involved with it, but today’s decision was the right one and allows David and his family to grieve together.”
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Sentencing Mr Hunter, judge Michalis Droussiotis said: “This is a crime that goes against human life, which is the highest virtue. Taking it is a crime.
“We are not facing a typical case. This is not a case acting out of animosity or differences between two people that led to someone taking another’s life.
“Before us is a unique case of taking human life on the basis of feelings of love, with the aim of relieving the person of their suffering that came due to their illness.”
Judge Droussiotis said there may never have been a case like this in Cyprus and the message for any future similar cases had to be that “taking away human life, even with the intention of relieving suffering, is a crime”.
He refused the defence team’s application to suspend Hunter’s prison sentence and said an immediate jail term was “unavoidable”.
But after passing the two-year sentence he said that Hunter would “soon be in a position to leave jail and live his life”, due to time already served.