One of the phone company doesn´t charge money for calls less than 60 seconds. Can I make my calls less than the 60 seconds to get free calls?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

If the law of the company allows this, then it is permissible for you to make calls within the permitted limit and not exceed it. This is because the company which offered this particularity knows that some subscribers will exploit it and it has approved of that in advance.

Allaah knows best.