OK caveat is you need to sign up for membership - which lasts a year.
20% discount applies to tariff including taxes, non-optional charges and small cabin bag (max: 42 x 32 x 25 cm) but excluding administration fee. This promotion applies on 10-11 December from 00.00 to 24.00 CET. Discount is only valid for new bookings up to 6 passengers.
Standard Membership (Member + 1 Companion) 29.99 EUR / year
Group Membership (Member + up to 5 Companions) 59.99 EUR / year