Eddie Howe had been keen on signing the Englishman this summer from Leicester and made him one of his top targets.
And he looks set to finally land his man after Newcastle reached an agreement with the Foxes on a fee worth more than £35million for his services.
talkSPORT understands Barnes has already agreed personal terms and is now close to joining Howe's side.
While the final pay structure is yet to be ironed out, it is only a matter of time before the winger becomes the second senior signing of the summer at St. James' Park.
And much of the fee is set to be paid for by the exit of Allan Saint-Maximin, who is closing in on a move to Saudi Arabia.
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Al Ahli, owned by PIF who also own Newcastle, are set to pay the Premier League side £20m for the Frenchman.
Saint-Maximin was a fan favourite at St. James' Park and had a close affinity with the supporters due to his party tricks on the pitch and down-to-earth personality off it.
Geordies will upset to see the winger leave after signing for the club in 2019 from OGC Nice while he has scored 13 times in 124 appearances and Howe wanted an upgrade.
He will join Edouard Mendy and Roberto Firmino at Al Ahli, who have also left the Premier League for the Saudi club.
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Barnes is set to become the latest arrival on Tyneside this summer, following the transfer of Sandro Tonali from AC Milan.
The 25-year-old was a top performer for Leicester despite their relegation from the Premier League.
He was the club's top scorer, scoring 13 times in 34 Premier League season and he looked certain to be sold after the Foxes dropped into the Championship.
The King Power Stadium outfit were happy to see him leave, for the right price at least, to cut down their wage bill.
They have now let a raft of players leave, including James Maddison, who joined Tottenham for over £40m.
Youri Tielemans, Caglar Soyuncu, Ryan Bertrand, Daniel Amartey, Ayoze Perez and Nampalys Mendy have all also left on free transfers after their contracts expired.
New Leicester boss Enzo Maresca has brought in Harry Winks and Conor Coady as they plot a way back to the Premier League at the first time of asking.
Barnes came up through the Leicester academy and made 187 appearances for the club after making his debut in 2016, scoring a total of 45 goals.