A 2013 article from Blastr reports that Smith started out at £200,000/year in 2009, and that he was making £1,000,000/year by 2013, which it says was David Tennant's salary when he left. A 2009 article from the Telegraph corroborates the initial £200,000/year deal for Smith, and the £1 million/year deal for Tennant at the time of his departure.
I couldn't find any results from Googling "Karen Gillan's salary on Doctor Who" or "Karen Gillan's salary for Selfie." But her entry on Celebrity Net Worth has her at $2 million -- take that as you will. To get a sense of what her salary might have been like for Selfie, I looked up typical sitcom star salaries and found this article from Deadline indicating that, before they negotiated salary increases in 2013, Big Bang Theory supporting stars Mayim Bialik and Melissa Rauch were making between $20,000-$30,000/episode, which is roughly $480,000-$720,000/year. Things are a little complicated, because Bialik and Rauch were supporting players rather than above-the-title stars of the show, while Gillan was not as well known to the American audience at large. However, Assuming she was making approximately $20,000/episode, Selfie's 13 episodes would have gotten Gillan around $260,000. Remember, also, that she was an above-the-line star (meaning, her name appeared before the title of the show) on Doctor Who for three seasons -- even if she was making half of Smith's salary, that would mean she made £100,000/year. Add to this her work on NTSF:SD:SUV::, Oculus, and Guardians of the Galaxy, and I promise you that she's rich, too.
Now, I'm not saying these guys are the richest of the rich. But the median income in the U.K. is $21,470 USD, and the median income in the United States is $50,756 USD. These guys -- Tennant, Smith, and Gillan -- all make way, way more than that. Their income may go up or down from year to year, but they are, by any reasonable definition, rich.
I couldn't find any results from Googling "Karen Gillan's salary on Doctor Who" or "Karen Gillan's salary for Selfie." But her entry on Celebrity Net Worth has her at $2 million -- take that as you will. To get a sense of what her salary might have been like for Selfie, I looked up typical sitcom star salaries and found this article from Deadline indicating that, before they negotiated salary increases in 2013, Big Bang Theory supporting stars Mayim Bialik and Melissa Rauch were making between $20,000-$30,000/episode, which is roughly $480,000-$720,000/year. Things are a little complicated, because Bialik and Rauch were supporting players rather than above-the-title stars of the show, while Gillan was not as well known to the American audience at large. However, Assuming she was making approximately $20,000/episode, Selfie's 13 episodes would have gotten Gillan around $260,000. Remember, also, that she was an above-the-line star (meaning, her name appeared before the title of the show) on Doctor Who for three seasons -- even if she was making half of Smith's salary, that would mean she made £100,000/year. Add to this her work on NTSF:SD:SUV::, Oculus, and Guardians of the Galaxy, and I promise you that she's rich, too.
Now, I'm not saying these guys are the richest of the rich. But the median income in the U.K. is $21,470 USD, and the median income in the United States is $50,756 USD. These guys -- Tennant, Smith, and Gillan -- all make way, way more than that. Their income may go up or down from year to year, but they are, by any reasonable definition, rich.