QuickLinks -- Click here to rapidly navigate through this document

Exhibit 12

QWEST CORPORATION
CALCULATION OF RATIO OF EARNINGS TO FIXED CHARGES
(UNAUDITED)

	Successor						Predecessor
	Six Months Ended June 30,		Year Ended December 31,		Nine Months Ended December 31,		Three Months Ended March 31,		Years Ended December 31,
	2013		2012		2011		2011		2010		2009
Income before income tax expense	$	831		1,391		892		490		1,873		1,921
Add: estimated fixed charges		269		513		342		171		689		705
Add: estimated amortization of capitalized interest		4		9		7		2		10		11
Less: interest capitalized		(8)		(18)		(5)		(3)		(12)		(10)
Total earnings available for fixed charges	$	1,096		1,895		1,236		660		2,560		2,627
Estimate of interest factor on rentals		13		28		38		18		62		63
Interest expense, including amortization of premiums, discounts and debt issuance costs		248		467		299		150		615		632
Interest capitalized		8		18		5		3		12		10
Total fixed charges	$	269		513		342		171		689		705
Ratio of earnings to fixed charges		4.1		3.7		3.6		3.9		3.7		3.7

QuickLinks

Exhibit 12