The following is a timeline of the first presidency of Donald Trump during the first quarter of 2018, from January 1 to March 31, 2018. For a complete itinerary of his travels, see List of presidential trips made by Donald Trump (2018). To navigate between quarters, see timeline of the Donald Trump presidencies. For the Q2 timeline see timeline of the first Trump presidency (2018 Q2).
According to FiveThirtyEight, President Trump's approval rate at the end of March was 40.5%, up 2% from the previous quarter and down 4.9% from the start of his presidency. For more polls, see 2018 opinion polling on the Donald Trump administration.