Revenue (Tables)

12 Months Ended

Dec. 31, 2021

Revenue [Abstract]

Summary of Revenue

	Year Ended December 31
	2019		2020		2021
	NT$		NT$		NT$
	(In Millions)
Revenue from contracts with customers	$	206,360	$	206,396	$	208,412
Other revenues
Government grants income		205		219		1,037
Rental income		818		843		864
Others		137		151		165
		1,160		1,213		2,066
Total	$	207,520	$	207,609	$	210,478

Summary of Disaggregation of Revenue

a. Disaggregation of revenue

2019

	Domestic Fixed Communi- cations Business		Mobile Communi- cations Business		Internet Business		International Fixed Communi- cations Business		Others		Total
	NT$		NT$		NT$		NT$		NT$		NT$
	(In Millions)
Main Products and Service Revenues
Mobile services revenue	$	—	$	58,703	$	—	$	—	$	—	$	58,703
Sales of products		1,957		35,545		41		265		3,785		41,593
Local telephone and domestic long distance telephone    services revenue		27,929		—		—		—		—		27,929
Broadband access and domestic leased line services    revenue		22,116		—		—		—		—		22,116
Data Communications internet services revenue		—		—		21,003		—		—		21,003
International network and leased line services    revenue		—		—		—		7,066		—		7,066
Others		13,064		1,142		8,790		4,144		810		27,950
	$	65,066	$	95,390	$	29,834	$	11,475	$	4,595	$	206,360

2020

	Domestic Fixed Communi- cations Business		Mobile Communi- cations Business		Internet Business		International Fixed Communi- cations Business		Others		Total
	NT$		NT$		NT$		NT$		NT$		NT$
	(In Millions)
Main Products and Service Revenues
Mobile services revenue	$	—	$	56,724	$	—	$	—	$	—	$	56,724
Sales of products		2,214		32,112		107		313		4,645		39,391
Local telephone and domestic long distance telephone    services revenue		26,475		—		—		—		—		26,475
Broadband access and domestic leased line services    revenue		22,420		—		—		—		—		22,420
Data Communications internet services revenue		—		—		21,447		—		—		21,447
International network and leased line services    revenue		—		—		—		3,884		—		3,884
Others		17,695		1,307		10,255		4,485		2,313		36,055
	$	68,804	$	90,143	$	31,809	$	8,682	$	6,958	$	206,396

2021

	Domestic Fixed Communi- cations Business		Mobile Communi- cations Business		Internet Business		International Fixed Communi- cations Business		Others		Total
	NT$		NT$		NT$		NT$		NT$		NT$
	(In Millions)
Main Products and Service Revenues
Mobile services revenue	$	—	$	58,048	$	—	$	—	$	—	$	58,048
Sales of products		2,173		35,414		128		12		5,180		42,907
Local telephone and domestic long distance telephone    services revenue		25,704		—		—		—		—		25,704
Broadband access and domestic leased line services    revenue		23,012		—		—		—		—		23,012
Data Communications internet services revenue		—		—		22,281		—		—		22,281
International network and leased line services    revenue		—		—		—		4,367		—		4,367
Others		13,255		1,222		10,428		4,246		2,942		32,093
	$	64,144	$	94,684	$	32,837	$	8,625	$	8,122	$	208,412

Summary of Contract Balances

b. Contract balances

	January 1,			December 31
	2020			2020			2021
	NT$			NT$			NT$
	(In Millions)
Trade notes and accounts receivable (Note 10)	$	26,408		$	22,622		$	23,947
Contract assets
Products and service bundling	$	6,943		$	7,232		$	7,197
Others		116			612			983
Less : Loss allowance		(17	)		(18	)		(18	)
	$	7,042		$	7,826		$	8,162
Current	$	4,441		$	5,331		$	5,554
Noncurrent		2,601			2,495			2,608
	$	7,042		$	7,826		$	8,162
Contract liabilities
Telecommunications business	$	12,772		$	13,602		$	13,144
Project business		10,360			6,687			5,435
Products and service bundling		39			16			4
Others		510			421			491
	$	23,681		$	20,726		$	19,074
Current	$	16,840		$	13,437		$	12,234
Noncurrent		6,841			7,289			6,840
	$	23,681		$	20,726		$	19,074

Summary of Changes in Contract Assets and Contract Liabilities

Significant changes of contract assets and liabilities recognized resulting from product and service bundling were as follows:

	Year Ended December 31
	2019			2020			2021
	NT$			NT$			NT$
	(In Millions)
Contract assets
Net increase of customer contracts	$	6,066		$	5,972		$	6,035
Reclassified to trade receivables		(6,405	)		(5,681	)		(6,039	)
	$	(339	)	$	291		$	(4	)
Contract liabilities
Net increase of customer contracts	$	22		$	7		$	—
Recognized as revenues		(89	)		(30	)		(12	)
	$	(67	)	$	(23	)	$	(12	)

Summary of Revenue Recognized

Revenue recognized for the period that was included in the contract liability at the beginning of the year was as follows:

	Year Ended December 31
	2019		2020		2021
	NT$		NT$		NT$
	(In Millions)
Telecommunications business	$	6,186	$	5,492	$	5,952
Project business		3,973		6,092		4,630
Others		404		512		431
	$	10,563	$	12,096	$	11,013

Summary of Incremental Costs of Obtaining Contracts

c. Incremental costs of obtaining contracts

	December 31
	2020		2021
	NT$		NT$
	(In Millions)
Noncurrent
Incremental costs of obtaining contracts	$	1,000	$	988