Northampton Saints chairman Leon Barwell hopes to apply for planning permission to expand Franklin's Gardens "within months".
The Premiership side filled their ground to 98% of its 13,500 capacity on average last season.
"Ideally we're going to be putting in for planning permission in a matter of months," Barwell told BBC Look East.
"If we can get the finance in place, we may be able to start that redevelopment as early as the end of this season."
It is still unclear where the financial backing will come from, but the club's accounts are in good health, with Saints posting a in the last financial year.
And Saints showed their potential to attract a big crowd in April, when more than 21,000 spectators watched them at Stadium MK in Milton Keynes.