National Underdog Day
Current observance references place National Underdog Day on the third Friday in December and attribute its creation to Peter Moeller.
Date and recurrence
Third Friday in December
This observance follows a reusable calendar rule rather than one fixed Gregorian date. The actual date can move from year to year. Rule: Third Friday in December each year.
Scope and status
The verified scope stored for this record is United States / informal recognition observance. The site preserves that boundary and does not infer broader government, global or public-holiday status from the observance name alone.
Also known as
National Underdog Day, Underdog Day
Topic and context
What this page does not assume
- Keep the source-defined country, community, organizer or institutional scope; do not silently broaden it.
- Do not treat the title alone as proof of government recognition or public-holiday status.
- Do not add a creator, founding story or origin claim unless the supporting evidence establishes it.
Sources
- Days Of The Year — National Underdog DayObservance Calendar
- Clearcover — National Underdog DayIndependent Company History
Frequently asked questions
When is National Underdog Day?
Third Friday in December The stored recurrence guidance is: Third Friday in December each year..
Does National Underdog Day fall on the same date every year?
It follows a recurring calendar rule, so the Gregorian date can change from year to year.
Is National Underdog Day an official public holiday?
The authority record verifies it within this scope: United States / informal recognition observance. That recognition does not by itself make it a statutory public holiday; the site only makes public-holiday claims when the supporting authority record explicitly does so.
Who established or recognizes National Underdog Day?
The stored designation basis is: Current observance references place National Underdog Day on the third Friday in December and attribute its creation to Peter Moeller.. Supporting provenance includes Days Of The Year — National Underdog Day. The site does not infer a separate creator or founder unless reviewed evidence establishes one.
Is National Underdog Day international or country-specific?
This authority record is country-scoped to United States. Its fuller verified scope is: United States / informal recognition observance.
How is this page verified?
The factual layer is source-backed and keeps its date rule, scope, provenance and editorial guardrails attached to the authority record. This record was checked on 2026-09-10.
Other observances on December 18
These records also resolve to December 18, 2026 under the current authority data.
Answer the Telephone Like Buddy the Elf Day
National Day Calendar places the observance on December 18, and National Today independently specifies every December 18.
Arabic Language Day
United Nations language observance
Guru Ghasidas Jayanti
High Court of Chhattisgarh calendars list Guru Ghasidas Jayanti on 18 December in both 2025 and 2026, supporting a stable December 18 date within that court-calendar scope.
International Migrants Day
A/RES/55/93
National Crime Junkie Day
Crime Junkie’s own fifth-anniversary page announced National Crime Junkie Day for December 18, 2022; subsequent observance references retain December 18 as the fan-community date.
National Day
Australia’s Department of Foreign Affairs and Trade current National Days protocol register lists Qatar — National Day on 18 December. The source verifies the diplomatic national-day identi…