When you pay for a HeavyMelon product, we ask for your credit card and billing address. That’s so we can charge you for service, calculate taxes due, and send you invoices. Your credit card is passed directly to our payment processor and doesn't ever go through our servers. We store a record of the payment transaction, including the last 4 digits of the credit card number and as-of billing address, for account history, invoicing, and billing support. We store your billing address to calculate any sales tax due in the United States or VAT in the EU, to detect fraudulent credit card transactions, and to print on your invoices.