Pontins has agreed to change its working practices after disclosure it had a blacklist of Irish surnames used to screen out bookings for its holiday parks from Gypsies and Travellers.
The Equality and Human Rights Commission (EHRC) investigated after being contacted by a whistleblower.
Pontins said it had now signed a legally binding agreement with the EHRC to stop discrimination.
News of the investigation was first report by the i news website.
The EHRC said Pontins had an “undesirable guests” list on its intranet of mainly common Irish names to identify people it did not want at its parks.
It said staff monitored calls and refused or cancelled bookings made by people with an Irish accent or surname, and Pontins’ commercial vehicle policy excluded Gypsies and Travellers from its holiday parks.
By declining to provide its services to guests of a certain race or ethnic group, Pontins was “directly discriminating on the basis of race” and breached the 2010 Equality Act, the EHRC said.
Alastair Pringle, executive director at EHRC, said: “It is hard not to draw comparisons with an ‘undesirable guests’ list and the signs displayed in hotel windows fifty years ago, explicitly barring Irish people and Black people.
“Banning people from services based on their race is discrimination and is unlawful. To say that such policies are outdated is an understatement.”
Pontins said it would “enhance staff training and procedures”, and would take measures “to promote equality throughout its business”.
As part of the agreement, Pontins must investigate the “undesirable guests” list, take appropriate action and ensure lessons are learned.
It must commission a review into its booking and commercial vehicle policy and consider any recommendations, and provide equality and diversity training for staff each year.