Allardyce's West Ham side will battle for promotion to the Premier League with Blackpool, with an estimated £90 million at stake for the winners.
Later in the evening Chelsea take on Bayern Munich as they bid to be crowned kings of Europe, but the Hammers boss claims the main event kicks off at 3pm at Wembley. "Saturday afternoon is bigger," he said.
"The Champions League final is a glory game, this is about your livelihood and your status. The Champions League is a big tournament but this one is about changing people's lives."
Meanwhile, Ian Holloway has paid tribute to the role of Fleetwood manager Micky Mellon in Blackpool's play-off charge.
The Seasiders' near neighbours will play in the Football League for the first time in their history next season after storming to the Blue Square Bet Premier title, and Holloway's Blackpool can give the Fylde coast a second promotion in as many months if they win at Wembley.
In the early months of the season, the prospect of an immediate return to the Barclays Premier League appeared unlikely as the Seasiders struggled to come to terms with the loss of key players such as DJ Campbell and Charlie Adam, and Holloway sought solace in Mellon - a former Blackpool midfielder in his playing days.
"I'd like to say we've earned it," said the 49-year-old. "We lost to Burnley away and I was pretty down, then had a phone call with Micky Mellon.
"Two days later we played Leeds away and we won 5-0. If I hadn't have had that conversation with him I'd still have been down in the dumps. I've never, ever wanted to feel sorry for myself, but I did then. Good gracious me, how far we've gone.
"The players, their reaction to what you commit to is vital and I came back in that following day talking about how we were going to pass it. We had nearly 700 passes in that game, which was phenomenal. I know they had a man short but it was brilliant."