Maygan Sensenberger, who is 23, is also charged with causing a disturbance.
She was expected to enter a plea in Saskatoon court Tuesday, but the case was adjourned until Thursday.
Sensenberger is married to Liberal Senator Rod Zimmer, 69, who has said he did not feel threatened.
It's alleged his wife said she would slit his throat during a ruckus on a flight from Ottawa to Saskatoon last month.
The couple have been ordered not to see each other, although they can talk over the phone, on the Internet or through a lawyer.
(CJME, The Canadian Press)