The closure of all Butlin’s, Haven holiday parks and Warner Leisure Hotels has been extended across the whole of the UK from April 17 to May 14.
The Bourne Leisure brands said the decision had been made following further government guidance during the coronavirus pandemic.
A Butlin’s spokesperson said: “It is with a heavy heart that we are announcing the closure of Butlin’s until 14th May. Our focus has always been to give our guests a fun and entertaining break, so it’s with much sadness that we do this.
“We are all facing unprecedented times – every person and every kind of work is affected. We will get through this and back to providing great breaks for you all. For now, we want to give you as much reassurance as possible, and remove any uncertainty you have for your break in this period.
“Our amazing contact centre team are ready to help you re-plan your break. We have given them the equipment and support to be able to work safely from home and we have brought in more people to help us get to your requests as quickly as possible.
“However, the scale of what we are dealing with is significant and it will mean it may take a little longer than usual, but they are all committed to and focused on helping everyone as quickly as they can.”
A Haven spokesperson said: “We are conscious that this will have an impact on a huge amount of families, and we are currently contacting all guests affected by the closure and the options that will be available to them.
“Due to the huge volumes of guests affected we are prioritising those who will be travelling between 17 April 2020 and 30 April 2020 first.
“We would like to thank our guests for their patience whilst we work through this as quickly as we can.
“The situation is being closely monitored and we ask guests to follow our social media channels and our website for latest updates.
“We would like to apologise to everyone for this disruption and thank our guests, owners and teams for their continued support.
“We do not intend to make any further statements as our priority now is to look after the guests affected by this decision.”
Warner customers with bookings before May 14 will have the full value of their breaks automatically moved into a hold account.
They are being given the option of rebooking and receiving a £100 voucher or a full refund.
Those booked with a third party, coach operator, travel agent or online booking agency, are being advised to contact them directly.