Upgrade: Start by logging into the billing website: https://billing.zetamex.com/index.php Navigate to your region package and put in a cancellation request. Please make a note in that request that you are upgrading your package. Then, order the new larger package you wish to purchase. It is probably more convenient to do this at the end of the month so as to not have extra charges for the new upgrade. Downgrade: In order to downgrade, your current package must have a compatible configuration as the new downgrade you wish. Example: You currently own a "Full Sim" package and wish to downgrade to a "Mini Sim". These 2 packages have the same types of region configurations in the package. If this is the case, then, complete the steps above except, in the "notes" during cancellation please make a note that you are downgrading. Then simply choose/purchase your new package. In other cases (incompatible packages), you will simply cancel your current package and order the new package. Any monies from the cancelled larger package will be applied to the new downgraded package, depending upon when the downgrade occurred during the monthly billing cycle.