No fees are charged for holding an account with Saxo, unless the account has been inactive for a prolonged period of time, in which an inactivity fee applies.
For accounts with no trading activity during a period of 6 consecutive months (180 days) an inactivity fee of USD 100.00 or equivalent in the account currency will be charged.
General information regarding Saxo commissions and pricing can be found here https://www.home.saxo/rates-and-conditions/commissions-charges-and-margin-schedule.