Components of the net periodic benefit costs for the three and six months ended June 30, 2016 and 2015 were as follows:



Pension Plans	Southern Company			Alabama Power			Georgia Power			Gulf Power			Mississippi Power
	(in millions)
Three Months Ended June 30, 2016
Service cost	$	62		$	15		$	18		$	3		$	3
Interest cost	101			24			34			4			5
Expected return on plan assets	(187		)	(46		)	(65		)	(8		)	(8		)
Amortization:
Prior service costs	3			—			2			1			—
Net (gain)/loss	37			10			13			1			1
Net cost	$	16		$	3		$	2		$	1		$	1
Six Months Ended June 30, 2016
Service cost	$	124		$	29		$	35		$	6		$	6
Interest cost	201			48			68			9			10
Expected return on plan assets	(374		)	(92		)	(129		)	(17		)	(17		)
Amortization:
Prior service costs	7			1			3			1			—
Net (gain)/loss	75			20			27			3			3
Net cost	$	33		$	6		$	4		$	2		$	2
Three Months Ended June 30, 2015
Service cost	$	64		$	15		$	18		$	3		$	3
Interest cost	111			27			39			5			6
Expected return on plan assets	(181		)	(44		)	(63		)	(8		)	(9		)
Amortization:
Prior service costs	7			1			2			—			1
Net (gain)/loss	54			13			19			2			2
Net cost	$	55		$	12		$	15		$	2		$	3
Six Months Ended June 30, 2015
Service cost	$	128		$	30		$	36		$	6		$	6
Interest cost	222			53			77			10			11
Expected return on plan assets	(362		)	(89		)	(126		)	(16		)	(17		)
Amortization:
Prior service costs	13			3			5			—			1
Net (gain)/loss	108			27			38			5			5
Net cost	$	109		$	24		$	30		$	5		$	6



Postretirement Benefits	Southern Company			Alabama Power			Georgia Power			Gulf Power			Mississippi Power
	(in millions)
Three Months Ended June 30, 2016
Service cost	$	6		$	2		$	1		$	1		$	1
Interest cost	17			4			7			—			1
Expected return on plan assets	(14		)	(7		)	(5		)	(1		)	(1		)
Amortization:
Prior service costs	1			1			1			—			—
Net (gain)/loss	4			1			2			—			—
Net cost	$	14		$	1		$	6		$	—		$	1
Six Months Ended June 30, 2016
Service cost	$	11		$	3		$	3		$	1		$	1
Interest cost	35			9			15			1			2
Expected return on plan assets	(28		)	(13		)	(11		)	(1		)	(1		)
Amortization:
Prior service costs	3			2			1			—			—
Net (gain)/loss	7			1			4			—			—
Net cost	$	28		$	2		$	12		$	1		$	2
Three Months Ended June 30, 2015
Service cost	$	5		$	2		$	1		$	—		$	1
Interest cost	20			5			9			1			1
Expected return on plan assets	(14		)	(7		)	(6		)	(1		)	(1		)
Amortization:
Prior service costs	1			—			—			—			—
Net (gain)/loss	4			1			3			—			—
Net cost	$	16		$	1		$	7		$	—		$	1
Six Months Ended June 30, 2015
Service cost	$	11		$	3		$	3		$	—		$	1
Interest cost	39			10			17			2			2
Expected return on plan assets	(29		)	(13		)	(12		)	(1		)	(1		)
Amortization:
Prior service costs	2			1			—			—			—
Net (gain)/loss	9			1			6			—			—
Net cost	$	32		$	2		$	14		$	1		$	2