Luton's home matches against Wycombe Wanderers this weekend and Oxford United on the final day of the campaign are both sold out in home sections.
A statement on the Hatters' official website said: "Should further tickets become available due to any returned tickets or unused away allocations then the Ticket Office will advise accordingly.
"Due to these sell outs the Ticket Office has now stopped selling pro-rata season tickets for the current season.
"Thank you all again for your tremendous support."
Town are yet to lose at home this season, taking 39 points from a possible 45, with 12 wins and three draws, while they have scored 38 goals and conceded just 11.