Ambassador Cruise Line is offering savings of up to 50% in its June campaign.
Valid for cruises departing on or after August 5, passengers will receive £50 per person per cruise in onboard credit for sailings of seven to 14 days, increasing to £75 for durations of 15-30 days, £100 for sailings of 31-50 days, and £250 for cruises of 51 days or more.
Children on multi-generational itineraries can sail for £1 on departures from London Tilbury.
More: Ambassador Cruise Line launches ‘amazing’ trade incentive
The 14-night Summer Balearics Getaway itinerary departs on August 12 and costs from £1,199 per adult and £1 per child.
Ambassador Cruise Line has introduced single supplements from 30% and is running a programme of events to allow solo passengers to meet each other.
Groups of 15 adults or more will receive a 5% discount on selected sailings, while groups of 25 will receive one free place, and groups of 50 will get two free places.
The line is also offering all passengers free matchday tickets to Essex Cricket Club when they make a booking as part of an ongoing partnership with the club.