Exhibit 12

Williams Partners L.P.

Computation of Ratio of Earnings to Fixed Charges

	Three months  ended March 31, 2013
	(Millions)
Earnings:
Income before income taxes	$	323
Less: Equity earnings, excluding proportionate share from 50% owned investees and unconsolidated majority-owned investees		(2	)
Income before income taxes and equity earnings		321
Add:
Fixed charges:
Interest incurred, including proportionate share from 50% owned investees and unconsolidated majority-owned investees		122
Rental expense representative of interest factor		2
Total fixed charges		124
Distributed income of equity method investees, excluding proportionate share from 50% owned investees and unconsolidated majority-owned investees		7
Less:
Interest capitalized		(17	)
Total earnings as adjusted	$	435
Fixed charges	$	124
Ratio of earnings to fixed charges		3.51