Castelo Branco District (Portuguese: Distrito de Castelo Branco [kɐʃˈtɛlu ˈβɾɐ̃ku] ) is located in Central Portugal. Its capital is Castelo Branco, which is now also its most populous city, overtaking Covilhã, which was once the largest city, in the late 2010s.

It has an area of 6,675 km (2,577 sq mi) (4th largest in Portugal), and a population of 225,916 inhabitants. It borders Spain.

The district is composed of 11 municipalities:

• Belmonte
• Castelo Branco
• Covilhã
• Fundão
• Idanha-a-Nova
• Oleiros
• Penamacor
• Proença-a-Nova
• Sertã
• Vila de Rei
• Vila Velha de Ródão

Summary of election results from Castelo Branco district, 1976-2022

Parties	%	S	%	S	%	S	%	S	%	S	%	S	%	S	%	S	%	S	%	S	%	S	%	S	%	S	%	S	%	S	%	S
	1976		1979		1980		1983		1985		1987		1991		1995		1999		2002		2005		2009		2011		2015		2019		2022
PS	36.4	3	27.8	2	30.3	2	37.1	3	18.5	1	22.4	2	32.4	2	53.2	3	51.6	3	46.1	3	56.0	4	41.0	2	34.8	2	38.9	2	40.9	3	47.7	3
PSD	22.6	2	In AD				30.6	2	31.2	3	52.1	4	51.8	3	32.1	2	32.0	2	38.3	2	26.7	1	29.8	2	37.9	2	In PàF		26.3	1	27.4	1
CDS-PP	19.9	2					13.2	1	9.6		4.7		3.9		7.2		6.3		7.1		5.3		8.4		9.6				3.7		1.6
AD			49.9	4	51.0	4
PRD									24.4	2	6.0
PàF																											35.3	2
Total seats	7		6										5										4
Source: Comissão Nacional de Eleições

39°49′26″N 7°29′31″W / 39.824°N 7.492°W / 39.824; -7.492