Manage payment options

Different billing address for add-ons
I’ve received a payment reminder. What should I do now?
Where can I find my invoices online?
How can I change my invoice address and payment data?
Methods of payment for membership and add-ons
How can I pay for my Premium membership and/or XING ProJobs with PayPal?
Can I deduct my membership payments from my taxes?
I'm having problems working out a transaction.