Philip V first exercised royal authority as regent after his brother Louis X died in 1316, while the widowed queen awaited the birth of a child. The infant John I survived only a few days. Philip then claimed the throne rather than allowing Louis's daughter Joan to succeed. Crowned at Reims in January 1317, he secured support for excluding women from the French succession.

Philip sought to strengthen royal finance and administration after years of war and poor harvests. He issued measures protecting the crown's domain from alienation, reorganized the royal household and defined the work of the Chamber of Accounts in 1320. He also pursued reforms in currency, weights and measures, consulting representatives of nobles, clergy and towns. These efforts aimed to make royal revenue and provincial government more consistent, though local interests limited what could be imposed.

His reign also saw violent persecution. The Shepherds' movement of 1320 attacked Jews in southern France, and the supposed leper conspiracy of 1321 brought arrests, executions and confiscations. Royal intervention formed part of the repression, which rested on accusations of poisoned wells rather than demonstrated conspiracy. Philip's surviving children were daughters, so the principle used to secure his own crown prevented them from inheriting it. When he died at Longchamp in January 1322, his brother Charles IV succeeded him.