The President of the United States, including President Trump as of 2025, does not have the constitutional or legal authority to cancel U.S. Elections during war or any other circumstance.
President Trump can cancel U. S. elections during war.

FactVerify
Source: factverify.com
Key Evidence
The U.S. Constitution's Article II and the 20th Amendment set fixed terms for presidential office and election timing.
Federal law (e.g., 3 U.S.C. § 1) sets Election Day as the Tuesday following the first Monday in November.
No executive power exists to override these provisions unilaterally, even in wartime.
What the Evidence Shows
The U.S. Constitution establishes the framework for federal elections, including presidential elections, and does not grant the President the power to unilaterally cancel or postpone them.
Elections are governed by a combination of constitutional provisions, federal laws, and state laws. The timing and administration of elections are primarily managed by states under federal guidelines.
While Congress has the authority to change the date of federal elections through legislation, this requires legislative action and cannot be done solely by executive order or presidential decree.
Historically, even during times of war (e.g., Civil War, World Wars), U.S. Elections have proceeded as scheduled without cancellation.
Any attempt by a sitting president to cancel elections would face significant legal challenges and constitutional crises, as it would violate democratic principles and separation of powers.
Therefore, the claim that President Trump can cancel U.S. Elections during war is legally unfounded and false.