You can change the price plan of your mobile subscription at any time via the website or the app. You will find this option under “product settings”.

TIP: 

Your current subscription bundles (i.e. data, sms and call) will expire at their foreseen expiration date. But when changing the price plan, you have the option to change it immediately or at the end of the current bundle period. 

If you still have plenty of data and/or calling minutes left, it is best to select the option “at the end of the current bundle period”. If you need more data and/or calling minutes, you can start the new subscription immediately. 

Only the bundles with the latest start date will be renewed. For example

My current bundles start on the 8th of the month. I renew or change my subscription on the 28th. The old bundles will remain active until the 8th of the next month, but will not be renewed. The subscription will continue from the 28th forward, with the 28th being the new renewal date.