Within thirty days after the SIM is activated, you can momentarily change the rate free. In other cases (end of period, repeated switching) the transition to the new fare must be paid. About the cost of a particular plan learn online operator.
Call the customer service of the company to the number 0890. MTS subscribers can contact customer service for free, so it's best to call from your own number. State the nature of your request and name your desired rate, or the requirements for it.
Go to the service "Internet assistant" on the website of the operator. Login ID is your own phone in ten digit format (without the eight). To receive the password, please, dial: *111*25#. After receiving the password, open the personal Cabinet.
Select the tab "management of the tariff plan and choose the most convenient. Confirm.