The FA has dropped a probe into allegations of racist chanting by Port Vale fans at a Bradford City game in August.
But the Vale Park club has been warned future incidents could result in sanctions including fines, closing parts of the ground, or even points docking.
Port Vale chairman Norman Smurthwaite said: “We will not tolerate racism or for that matter other behaviour that brings our club into disrepute.
“Any supporter found to have misbehaved in this way will face a lifetime ban if found guilty.”
Supporters group chairman Ally Simcock added: “We are not racist fans and this was an isolated incident. However, we have all been tarnished by this.
“It is of utmost importance we work together in stamping out discrimination of any kind, as the consequences could dramatically affect the whole club, from the players to the fans.
“It is something none of us should tolerate at our club. Let’s unite, move forward and show the football community what the fans of this club are really about.”
Fans have been encouraged to report any incidents of racist behaviour via the information on the “kick it out” hoardings throughout the stadium.