The tickets are sent to your email address when they are confirmed by the operator.
There are two types of confirmations: instant and manual.
Operators who confirm bookings instantly are connected to our systems directly, confirmation is done automatically shortly after booking has been placed. Such operators have an instant badge (little lightning icon) on their trips.

Operators that are not connected to our systems directly confirm bookings manually, meaning, a staff worker at their end will go through all the bookings and confirm them one by one. As you can imagine, this process is more time consuming, and it will take longer for such bookings to become confirmed. Operators who employ this system have specific deadlines for confirmation. For example, some promise to confirm the booking within 24 hours after it has been placed but no earlier than 3 weeks before the departure date etc. If you place booking months and months in advance, it may take several months as well to receive the confirmation of your trip.