Over 65,000 fans are set for Wembley, in a match that sees the winner clinch a spot in the Sky Bet Championship.
Barnsley sealed their place in the capital with a 2-1 aggregate victory over Bolton Wanderers.
Sheffield Wednesday, meanwhile, secured their spot by completing the unthinkable and came back from a 4-0 first-leg defeat at Peterborough to level the tie 5-5 on aggregate in the second leg- and then went on to win the game on penalties.
In the previous meetings between the sides this season Barnsley have won both, with a 2-0 win at Hillsborough back in August and a 4-2 victory in the reverse fixture in March.
Michael Duff has rejuvenated his squad from the disappointing season last time out and the chance of automatic promotion was only just ruled out a few weeks ago- following defeat to eventual second-placed Ipswich.
If the game finishes level after 90 minutes, extra time and penalties will then pursue.
Barnsley have received one penalty this season and missed it.
Wednesday have received 11 penalties, scoring nine and missing two.
Head coach Michael Duff has a fully fit squad at his disposal for the game on Monday.
Conor McCarthy remains a long-term absentee and is set to return for pre-season.
George Byers, who had been previously been ruled out for the season, could feature in some form though it is likely he will not start.
Despite scoring the winning penalty, Jack Hunt is set to begin from the bench.
Isted; Thomas, Andersen, Kitching, Williams, Kane, Connell, Phillips, Cadden, Cole, Tedic.
Dawson; Iorfa, Ihiekwe, James, Palmer, Vauks, Bannan, Johnson, Windass, Gregory, Smith.
Barnsley - Luca Connell
Luca Connell has been instrumental to Barnsley's season. His ability to protect the defence, whilst also creating attacks has proved important.
Barnsley's No. 48 has grabbed two goals and nine assists in 41 league appearances this season. He has proven a steal since signing on free from Celtic in the summer transfer window.
Connell impressed in the 4-2 victory game at home to Sheffield Wednesday earlier this season and ran the show so fans will be hoping for a repeat performance.
Sheffield Wednesday - Barry Bannan
Sheffield Wednesday's captain and key player, Barry Bannan, will hope it is second time lucky at Wembley.
He was part of the 2016 defeat to Hull City in the Sky Bet Championship Final at the National Stadium.
Bannan has been crucial in the midfield for the Owls, contributing with 13 assists and seven goals in the league. Wednesday's no.10 has stepped up in the big games this season.
Where is the game being played?
The game is being played at Wembley Stadium, the national stadium of England. It is a 116-mile journey from Hilsbourhg for Wednesday fans and a 172-mile journey from Oakwell for Reds fans.
What time is the kick-off?
The fixture on Bank Holiday Monday will kick off at 15:00 BST.
How can I watch it?
Those watching from the UK can watch the game live on Sky Sports Football, with coverage starting from 14:00 BST on the Main Event and Football channel.