Just in case Trump were to leave office any time soon, here’s a list of his successors, as outlined in The Succession Act 1947.
Obviously, Trump's presidency is going really, really smoothly with absolutely no troubles.
That Iran nuclear deal looks to have been a top bit of business from the POTUS, ish, but that FBI investigation isn't exactly going away.
Whether Trump will get impeached remains to be seen - but no one was ever hurt by thinking hypothetically.
So Who Becomes President If Trump Is Impeached?
US law provides a very extensive line of succession should a President for any reason be unable to fulfill his obligations as President, That line is:
1. Vice President Pence
2. House Speaker, Paul Ryan
3. President pro tempore of the Senate, Orrin Hatch
4. Secretary of State, Mike Pompeo
5. Treasury Secretary, Steven Mnuchin