The deceased had been removed to Naas General Hospital for autopsies which were completed yesterday. The results show both died as a result of gunshot wounds.
The couple, John Deegan, aged 53, from Cloghan, Co Offaly, and Deirdre Keenan, aged 51, from Naas, Co Kildare, died late on Sunday night or early on Monday morning at Stonehaven B&B in Carlow Town.
It is thought Mr Keegan, a separated father of two, first shot Ms Keenan, a separated mother of six, with his legally held shotgun before turning the gun on himself.
The pair, who began a relationship last year, had been socialising in the town since Saturday and visited two or three local pubs on Sunday before retiring to the B&B, where they were the only guests.
A shocked member of the family that owns the premises, along with the Stonehaven pub across the road, found their bodies after calling to carry out housekeeping duties at lunchtime on Monday.
Customers of the Stonehaven pub who are thought to have been the last to see the couple alive are being questioned by investigating gardaí, but it is understood nobody noticed anything unusual about their behaviour.
Detectives are hoping that phonecalls made by the couple in the time they were away might help them understand the motive for the incident. They are also trying to establish if Mr Deegan normally brought his shotgun with him when he travelled.
Ms Keenan was originally from Naas and was well known and popular in the town where she lived all her life. A mother of six adult children, including triplets, she had separated from her husband Charlie in recent years.
Mr Deegan was also well known and respected in his home county. Originally from Cadamstown in Co Offaly, he had more recently lived between Ballycumber and Cloghan, and only separated from his wife Eileen about a year ago.