As prime minister, Philippe led the centrist LREM–MoDem coalition into the 2017 French legislative election that returned his government with a sizeable majority in the National Assembly.

In 2021, a year after the end of his premiership, Philippe founded the centre-right Horizons party, which then became part of the governing Ensemble coalition in the context of the 2022 French legislative election.

During his time in office, Philippe oversaw the passage of a package of labour law and taxation system reforms as part of Macron's self-proclaimed "pro-business" agenda.

[8] In his years at Sciences Po, Philippe supported Michel Rocard and was influenced by him, identifying with the Rocardian and social democratic wings of the Socialist Party.

[7] Recognising the ideological proximity between Michel Rocard and Alain Juppé, Philippe supported the latter at the time of the creation of the Union for a Popular Movement (UMP) in 2002, marking the end of his left-wing activism;[7] the same year, he failed to win his constituency in the 2002 French legislative election.

[9] He served under Juppé as director general of services of the UMP until 2004, when the mayor of Bordeaux was convicted as a result of the fictitious jobs case implicating the Rally for the Republic (RPR).

He then took a job in the private sector, working with the American law firm Debevoise & Plimpton,[6][7] and was elected to the regional council of Upper Normandy the same year.

He formed the Second Philippe government on 21 May 2017 following a series of resignations after scandal embroiled ministers François Bayrou,[17] Sylvie Goulard, Marielle de Sarnez and Richard Ferrand.

[21] Following the vote, Philippe addressed the parliament, talking about plans to tackle France's debt by raising cigarette tax and cutting spending.

The plan attempts to speed up asylum claims from fourteen months to six, provide housing for 7,500 refugees by the end of 2019, improve living conditions for minors and deport economic migrants.

[33] In April 2024, police searched Philippe's office premises as part a preliminary probe opened in December 2023 on charges of influence peddling, favouritism, misappropriation of public funds and psychological harassment.

Furthermore, he is one of a few French prime ministers in the last century (Henri Queuille, Raymond Barre, François Fillon, and Jean-Marc Ayrault) to be older than the president he served under, by an unprecedented seven years.

As prime minister, Philippe announced that he had vitiligo, a skin disease responsible for the noticeable asymetrical white patch of hair on his beard.