Stevenage chairman Phil Wallace believes promotion to the Championship would see them recognised as a "real football club".
Boro are at home to Wigan Athletic on Saturday and a win will guarantee their place in the League One play-offs.
If they lose or draw, they could be pipped by Luton Town or Plymouth Argyle, who both have a superior goal difference.
Stevenage last reached the third-tier play-offs in 2012 and Wallace told BBC Three Counties Radio: "Saturday is probably the biggest game in our history because when we were here 14 years ago I'm not sure that we believed we could do it.
"Certainly we'd never have been ready for Championship football, but now we do believe we can do it – and we are ready for it.
"This is the biggest game Stevenage have ever had. I know people might disagree with that, but from where I sit it, it feels like it."
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Stevenage were promoted into the English Football League in 2010 but have never been higher than League One since then.
They were held to a 1-1 draw at Doncaster Rovers last weekend, which enabled Luton to close the gap to just a single point, and Plymouth to two points following 2-1 home wins over Barnsley and Port Vale respectively.
Winning promotion could be worth as much as £10m to the club.
"It's much more expensive to play in the Championship than it is in League One and League Two, the players wages are completely different," said Wallace.
"But it's where you want to be. In everything you do, you're always striving for success, trying to get to the top of your particular tree – and that's our particular tree, Championship football.
"Luton are a historically big club but they came from the National League and went right the way through (to the Premier League) with the same kind of infrastructure.
"We believe we're ready for this now. We'd probably have to be authentic in our approach to it, as we are in everything, but it would be a fantastic achievement and great for the town – we would have arrived as a real football club at a very high level."
Stevenage were almost relegated out of the EFL in 2020 but kept their place by virtue of Macclesfield Town being deducted points.
They won promotion under Steve Evans, now Bristol Rovers boss, in 2023 and are now hoping to go one step further under his successor Alex Revell.
Wallace said: "If you've got settled management and settled ownership then you tend to do much better – that's what you've probably been seeing (in the last few years).
"Steve came in, we started to settle everything down, we had some consistency in our decision-making – we did need to introduce some more money into the club but it's the consistency that's got us really to where we are now."
