Mr Key declared 22 gifts, many related to his love of golf.
He was twice flown by helicopter to the Kauri Cliffs golf course in Northland by Bell Investment Trust, with accommodation and golf included on one occasion.
Businessman Gary Lane shouted Mr Key helicopter transport, accommodation and golf at his luxurious Wairakei Resort near Taupo.
Mr Lane's worth was estimated last year at $300 million.
Multimillionaire investor Trevor Farmer also chipped in with helicopter flights and a round of golf at Kauri Cliffs.
President Obama gave the Prime Minister a golf putter and golf balls.
The two leaders played golf together in Hawaii, where they both have holiday homes, in January last year.
Lord Ashcroft, a philanthropist and businessman, shouted the Prime Minister a private plane trip from London to Sarajevo, the capital of Bosnia and Herzegovina, and from there to Davos, Switzerland.
Mr Key chaired an International Democrat Union executive committee meeting in Sarajevo on January 21, which Lord Ashcroft also attended.
The organisation is made up of more than 50 centre-right political parties from around the world.
The register also shows that North Shore MP Maggie Barry was given three tickets to the Rolling Stones concert by Regional Facilities Auckland.
According to the register, fellow National MP Judith Collins received two tickets to a Bruce Springsteen concert from council-controlled organisation Auckland Tourism Events and Economic Development, which also gave her two tickets to a boxing match between Joseph Parker and Brian Minto.
However, ATEED spokesman Steve Armitage said the organisation had not supplied the tickets to Ms Collins.
Today Ms Collins said she had been advised the declaration was incorrect, and that the Springsteen tickets were a gift from Regional Facilities Auckland, and the boxing was a gift from promoters Duco.
"A correction will be sent to the Registrar once I have sighted the paperwork."
Other sports fans in Parliament included Labour MPs Kelvin Davis, who got boxing tickets from Sky TV and a corporate box at the Auckland Nines from the NZ Warriors, and David Cunliffe, who went to an All Blacks game courtesy of NZ Rugby.
Labour's Louisa Wall and Trevor Mallard also received tickets and hospitality from NZ Rugby and NZ Rugby League.
National list MP Melissa Lee was given golfing gear by Kiwi superstar Lydia Ko, and Labour leader Andrew Little attended the Womad festival this year, paid for by the Taranaki Arts Festival Trust.
NZ First list MP Darroch Ball was the only MP to declare no pecuniary interests.