When the game was released, it required a mandatory subscription costing € 12.99 per month. As of March 17, 2015, the game no longer requires any payment of the monthly game fee. This fee has been replaced by the ESO Plus, a completely optional subscription that gives access to all DLCs until their expiration. The price is the same as the previous one. Anyone who purchases the game gets 30 days of play included. To take advantage of it, however, users must first choose, when creating an account, a means of payment and a subscription plan; which will become effective once the 30 days of included play have been exhausted.
People who opt for a payment method that automates the renewal of their subscription (such as credit cards) are then informed that they will not be debited until the 30 days of included play have reached their date term. They are also informed that they can delete the means of payment that they have registered before the period of 30 days of play included expires.
To purchase a subscription, you can login to your account and click on BUY NOW button. You can pay via your credit card, bank, PayPal, debit card, etc.