Who is the last prophet in Catholicism?

OP: Who is the last person regarded as a true prophet in Catholicism? What was his time frame?

There is no last prophet in Catholicism.

The Catholic Church believes the office of prophet continues from Christ's time as He fulfilled the tri-roles of Prophet, Priest, King. Thus, as believers, we may be prophets.

Participation in Christ's prophetic office

904 "Christ . . . fulfills this prophetic office, not only by the hierarchy . . . but also by the laity. He accordingly both establishes them as witnesses and provides them with the sense of the faith [sensus fidei] and the grace of the word"438

To teach in order to lead others to faith is the task of every preacher and of each believer.439

905 Lay people also fulfill their prophetic mission by evangelization, "that is, the proclamation of Christ by word and the testimony of life." For lay people, "this evangelization . . . acquires a specific property and peculiar efficacy because it is accomplished in the ordinary circumstances of the world."440

This witness of life, however, is not the sole element in the apostolate; the true apostle is on the lookout for occasions of announcing Christ by word, either to unbelievers . . . or to the faithful.441

906 Lay people who are capable and trained may also collaborate in catechetical formation, in teaching the sacred sciences, and in use of the communications media.442

907 "In accord with the knowledge, competence, and preeminence which they possess, [lay people] have the right and even at times a duty to manifest to the sacred pastors their opinion on matters which pertain to the good of the Church, and they have a right to make their opinion known to the other Christian faithful, with due regard to the integrity of faith and morals and reverence toward their pastors, and with consideration for the common good and the dignity of persons."443 Catechism of the Catholic Church

Paragraph 907 was used by Dorothy Day and others during Second Vatican Council.

Some people would claim that Dorothy Day has been, in the history of the Church in the United States, the most outstanding of prophets. She started an organization or community, the Catholic Worker Community, people who live the radical teachings of the Gospel, who go among the poor and live among them, welcoming the poor into their homes through houses of hospitality, and who try to transform our world into the Reign of God by bringing the message of Jesus into our world.

One of the things that Dorothy Day did that was not well known, during the Second Vatican Council, when the Bishops at the Council were discussing the part of the document on the Church in the modern world about war and peace, she together with some others, met with a number of bishops and helped to influence their thinking about the need to issue a declaration condemning weapons of mass destruction. It’s the only place in all of the Vatican Council, in the document of the Church in the modern world, where there is a condemnation of weapons of mass destruction as being something totally evil that never could be justified. -Source-

So, to again answer the OP, there is no last prophet in Catholicism. Thus, as to the second question, there is no "time frame" but from Christ's ascension to today.

The last major prophet who predicted a specific and verifiable event is Sr. Lucia of Fatima.

Lucia dos Santos is one of the seers, along with Jacinta and Francesco Marto, who saw a vision of the Blessed Virgin on May 13th 1917 and each of the following months. 9-year-old Lucia asked the Blessed Virgin to confirm her apparition with a public miracle and Lucia related to the public that on October 13th 1917 the miracle will take place.

The miracle of the Sun happened as prophesied and was seen by around 70,000 people and widely reported and attested by secular and anti-clerical media.

The Church has determined her revelations as worthy of belief. Although it is not required for a Catholic to accept any private revelation it would be imprudent to reject the revelation at Fatima since it is accompanied by the largest public miracle since the Resurrection.

The purpose of Our Lady's revelation was to ask for daily prayer of the Rosary and penance to avert a coming calamity that will befall the Church.

Sr. Lucia stated that what this calamity is must be revealed by the Pope before 1960 since it will already be clear then.

Unfortunately, the secret revealed to Lucia was not revealed by neither John XXIII, Paul VI, John Paul I, John Paul II, Benedict XVI, nor Francis I.

How is it possible that supposed Catholics would disobey a direct command from the Mother of God? That is out of scope for this question but if you're interested the whole story is presented here.

If you'd like to learn even more there is a great book by the eminent historian William Thomas Walsh Our Lady of Fatima.

Who is the last prophet in Catholicism?

I take it you are not asking about biblical Prophets, but those regarded as saints or holy individuals.

I will not deal with Scriptural Prophets as Mary's answer has already done that.

This is one of those questions which in all likelihood will have to continually be updated as time moves forward. The ultimate (future) last prophet in Catholicism may never actually ever be known.

And it shall come to pass, in the last days, (saith the Lord,) I will pour out of my Spirit upon all flesh: and your sons and your daughters shall prophesy, and your young men shall see visions, and your old men shall dream dreams. - Acts 2:17

As such as it may be I would like to postulate as of today, January 31, 2023, that the last prophet in Catholicism would be the late Pope Benedict XVI, who died December 31,2022.

The only other Pope to died on December 31st (335) was Pope Saint Silvester I, who brought in a new age into the Church. So too, I believe Pope Benedict will be responsible for welcoming the next new age into the Church. It is not like I have not thought of this before: Pope Benedict XVI and Pope Francis and the Prophecy of the Popes?

The Church is not usually in the habit of bestowing the title of prophet on her children, even when it is obvious that certain individuals do have a particular gift of prophecy.

Way before becoming pope, or even a prelate, Ratzinger laid it out in a 1969 broadcast on German radio for all to hear ...

He didn’t pretend he could tell the future. No. He was much too wise for that. As a matter of fact, he tempered his initial remarks with this disclaimer:

“Let us, therefore, be cautious in our prognostications. What St. Augustine said is still true: man is an abyss; what will rise out of these depths, no one can see in advance. And whoever believes that the Church is not only determined by the abyss that is man, but reaches down into the greater, infinite abyss that is God, will be the first to hesitate with his predictions, for this naïve desire to know for sure could only be the announcement of his own historical ineptitude.”

But his era, brimming with existential danger, political cynicism and moral waywardness, hungered for an answer. The Catholic Church, a moral beacon in the turbulent waters of its time, had recently experienced certain changes of its own with adherents and dissenters alike wondering, “What will become of the Church in the future?”

10 Pithy and Potent Quotes from Pope Benedict

And so, in a 1969 German radio broadcast, Father Joseph Ratzinger would offer his thoughtfully considered answer. Here are his concluding remarks,

“The future of the Church can and will issue from those whose roots are deep and who live from the pure fullness of their faith. It will not issue from those who accommodate themselves merely to the passing moment or from those who merely criticize others and assume that they themselves are infallible measuring rods; nor will it issue from those who take the easier road, who sidestep the passion of faith, declaring false and obsolete, tyrannous and legalistic, all that makes demands upon men, that hurts them and compels them to sacrifice themselves. To put this more positively: The future of the Church, once again as always, will be reshaped by saints, by men, that is, whose minds probe deeper than the slogans of the day, who see more than others see, because their lives embrace a wider reality. Unselfishness, which makes men free, is attained only through the patience of small daily acts of self-denial. By this daily passion, which alone reveals to a man in how many ways he is enslaved by his own ego, by this daily passion and by it alone, a man’s eyes are slowly opened. He sees only to the extent that he has lived and suffered. If today we are scarcely able any longer to become aware of God, that is because we find it so easy to evade ourselves, to flee from the depths of our being by means of the narcotic of some pleasure or other. Thus our own interior depths remain closed to us. If it is true that a man can see only with his heart, then how blind we are!

“How does all this affect the problem we are examining? It means that the big talk of those who prophesy a Church without God and without faith is all empty chatter. We have no need of a Church that celebrates the cult of action in political prayers. It is utterly superfluous. Therefore, it will destroy itself. What will remain is the Church of Jesus Christ, the Church that believes in the God who has become man and promises us life beyond death. The kind of priest who is no more than a social worker can be replaced by the psychotherapist and other specialists; but the priest who is no specialist, who does not stand on the [sidelines], watching the game, giving official advice, but in the name of God places himself at the disposal of man, who is beside them in their sorrows, in their joys, in their hope and in their fear, such a priest will certainly be needed in the future.

“Let us go a step farther. From the crisis of today the Church of tomorrow will emerge — a Church that has lost much. She will become small and will have to start afresh more or less from the beginning. She will no longer be able to inhabit many of the edifices she built in prosperity. As the number of her adherents diminishes, so it will lose many of her social privileges. In contrast to an earlier age, it will be seen much more as a voluntary society, entered only by free decision. As a small society, it will make much bigger demands on the initiative of her individual members. Undoubtedly it will discover new forms of ministry and will ordain to the priesthood approved Christians who pursue some profession. In many smaller congregations or in self-contained social groups, pastoral care will normally be provided in this fashion. Along-side this, the full-time ministry of the priesthood will be indispensable as formerly. But in all of the changes at which one might guess, the Church will find her essence afresh and with full conviction in that which was always at her center: faith in the triune God, in Jesus Christ, the Son of God made man, in the presence of the Spirit until the end of the world. In faith and prayer she will again recognize the sacraments as the worship of God and not as a subject for liturgical scholarship.

“The Church will be a more spiritual Church, not presuming upon a political mandate, flirting as little with the Left as with the Right. It will be hard going for the Church, for the process of crystallization and clarification will cost her much valuable energy. It will make her poor and cause her to become the Church of the meek. The process will be all the more arduous, for sectarian narrow-mindedness as well as pompous self-will will have to be shed. One may predict that all of this will take time. The process will be long and wearisome as was the road from the false progressivism on the eve of the French Revolution — when a bishop might be thought smart if he made fun of dogmas and even insinuated that the existence of God was by no means certain — to the renewal of the nineteenth century. But when the trial of this sifting is past, a great power will flow from a more spiritualized and simplified Church. Men in a totally planned world will find themselves unspeakably lonely. If they have completely lost sight of God, they will feel the whole horror of their poverty. Then they will discover the little flock of believers as something wholly new. They will discover it as a hope that is meant for them, an answer for which they have always been searching in secret.

“And so it seems certain to me that the Church is facing very hard times. The real crisis has scarcely begun. We will have to count on terrific upheavals. But I am equally certain about what will remain at the end: not the Church of the political cult, which is dead already, but the Church of faith. It may well no longer be the dominant social power to the extent that she was until recently; but it will enjoy a fresh blossoming and be seen as man’s home, where he will find life and hope beyond death.

The Catholic Church will survive in spite of men and women, not necessarily because of them. And yet, we still have our part to do. We must pray for and cultivate unselfishness, self-denial, faithfulness, Sacramental devotion and a life centered on Christ. - When Father Joseph Ratzinger Predicted the Future of the Church

Some may believe that we are now in the end times, like myself, even though no one know the day or the hour the world as we know it will cease to exist, but then Pope Emeritus Benedict XVI may have more than just a few words to say on this subject matter: The Mystery of Evil: Benedict XVI and the End of Days

In 2013, Benedict XVI became only the second pope in the history of the Catholic Church to resign from office. In this brief but illuminating study, Giorgio Agamben argues that Benedict's gesture, far from being solely a matter of internal ecclesiastical politics, is exemplary in an age when the question of legitimacy has been virtually left aside in favor of a narrow focus on legality. This reflection on the recent history of the Church opens out into an analysis of one of the earliest documents of Christianity: the Second Epistle to the Thessalonians, which stages a dramatic confrontation between the "man of lawlessness" and the enigmatic katechon, the power that holds back the end of days. In Agamben's hands, this infamously obscure passage reveals the theological dynamics of history that continue to inform Western culture to this day.

The following articles may be of interest to some:

• Joseph Ratzinger's Prophetic Outlook for the Church (YouTube video)

• Benedict XVI: It Is The Time Of Antichrist

• Ex-pope Benedict XVI links gay marriage, abortion with the Antichrist in new book

More often than not prophetic words are not truly realized as being prophetic until after the events prophesied become reality. The same holds true for Catholic prophets, but there is good reason that Pope Emeritus Benedict XVI words will come to pass.

Remembering the day when lightning struck at the Vatican

Later Catholic prophets will follow as time passes on!