Those who are not Catholic can be saved. It is a general theological principle that God gives all men an opportunity for salvation, since he wills all men to be saved (1 Tim 2:4), and he is a just God.
Sections 846-848 of the Catechism deal specifically with the doctrine of no salvation outside the Church.:
846 How are we to understand this affirmation, often repeated by the Church Fathers?335 Re-formulated positively, it means that all salvation comes from Christ the Head through the Church which is his Body:
Basing itself on Scripture and Tradition, the Council teaches that the Church, a pilgrim now on earth, is necessary for salvation: the one Christ is the mediator and the way of salvation; he is present to us in his body which is the Church. He himself explicitly asserted the necessity of faith and Baptism, and thereby affirmed at the same time the necessity of the Church which men enter through Baptism as through a door. Hence they could not be saved who, knowing that the Catholic Church was founded as necessary by God through Christ, would refuse either to enter it or to remain in it.336
847 This affirmation is not aimed at those who, through no fault of their own, do not know Christ and his Church: Those who, through no fault of their own, do not know the Gospel of Christ or his Church, but who nevertheless seek God with a sincere heart, and, moved by grace, try in their actions to do his will as they know it through the dictates of their conscience - those too may achieve eternal salvation.337
Even the Fathers of the Second Vatican Council taught: “We believe that this one true religion continues to exist in the Catholic and Apostolic Church, to which the Lord Jesus entrusted the task of spreading it among all people (Mt 28:19-20)…all persons are required to seek the truth, and when they come to know it, to embrace it and hold fast to it” (Second Vatican Council, Declaration Dignitatis humanae, 1.).
Concerning the salvation of non-Catholic Christians, the *Catechism of the Catholic Church * (1260) says “Every man who is ignorant of the Gospel of Christ and of his Church, but seeks the truth and does the will of God in accordance with his understanding of it, can be saved.” It is not a salvation outside of Christ, but one through his grace.
Thus, a faithful Protestant, who truly seeks God, but who had seen no evidence or insufficient evidence for the Catholic faith, such a person could be innocently ignorant. On the other hand, if a faithful Protestant, who truly seeks God, knew in his heart the truths of the faith, he would become a Catholic (as I did). Whereas, if a Protestant is not ignorant of the Gospel of Christ and of his Church, but knowingly and willingly rejects the truth and dies outside of it, he cannot be saved. In short, what you know can hurt you.
Further reading on this subject:
Dominus Iesus: vatican.va/roman_curia/congregations/cfaith/documents/rc_con_cfaith_doc_20000806_dominus-iesus_en.html
You’ll find many excellent articles on this subject at the following sites: ic.net/~erasmus/RAZ419.HTM.
“Salvation outside the Church”:
“No Salvation Outside the Church” by Father William Most
God bless you! You are in my prayers.