Architectural historian, Dr William Napier, who carried out the detailed heritage survey, told BBC Scotland: "If Burns walked through the gate today he would recognise the farm he established."
The £12,000 study of Ellisland Farm funded by Historic Environment Scotland was announced last year and revealed the Burns site required £500,000 worth of repairs.
Burns wrote some of his most famous works – including nature poems inspired by his surroundings – at Ellisland from 1788 to 1791.
Dr Napier, a building surveyor in Peebles, said: "During that period of research we understand much more of the farm's development - that he was responsible for building more of the buildings than previously thought.
"After he left, the farm obviously was developed and new buildings were added, but essentially we can be confident that if Burns walked through the gate today he would recognise the farm that he established.
"We think now we can be confident that Ellisland Farm is probably the most authentic site associated with Burns' lifetime and I think that that makes it a really important place."
It was previously thought that Burns was only responsible for the farmhouse.
However, the research suggests that both the barn and the byre and stable were also his work.
Dr Napier said it was a "hidden gem" but extensive work on the site was needed.
"Although it needs a lot of repairs it could have been an awful lot worse," he said. "This farm has avoided the large agricultural buildings and knocking down of older farmsteads.
"We are very fortunate that although there are a lot of repairs required the farm is in good heart. In terms of authenticity this is unparalleled and Burns would recognise it if he was able to come back today."
There will be an online event named ‘Secrets of Ellisland Revealed’ about the investigation on Wednesday, January 26 – a day after Burns Night.
The talk will feature Dr Napier who will reveal the discoveries made in the study.
There will also be contributions from experts Professor Gerard Carruthers, Dr David Hopes and Dr Gerard McKeever.