Basic Points are used to determine which EuroBonus membership level you are eligible for. In order to become a Silver-member you need to earn 20 000 Basic Points in your qualification period, and in order to become a Gold-member you need to earn 50 000 Basic Points in your qualification period.
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You can only convert points into Basic Points on this website, not by contacting EuroBonus member service or through any other channel.
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It is the date that you placed your order on this website that determines whether you are eligible for Silver- or Gold-membership, not the date that the Basic Points are credited to your account.