Thomson and sister brand First Choice has said a back office technical problem which had prevented it sending confirmations to customers has now been rectified.
The issues first emerged last week but did not prevent customers from booking online, over the phone or in store with the UK’s leading tour operator.
For a period last week the firm’s travel agents were forced to use an alternative system to make bookings.
A spokeswoman said: “Thomson and First Choice can confirm that after experiencing some technical issues last week, our back office systems are now up and running.
“All distribution channels (online, retail, call centre) are now functioning for booking enquiries including new bookings, payments and amendments.”