The following table presents the impact on Ameren Missouri and Ameren Illinois of related party transactions for the years ended December 31, 2012, 2011, and 2010. It is based primarily on the agreements discussed above and the money pool arrangements discussed in Note 4 - Short-term Debt and Liquidity.



Agreement	Income Statement Line Item		Ameren Missouri		Ameren Illinois
Ameren Missouri power supply agreements	Operating Revenues	2012	$(b)		$(a)
with Ameren Illinois		2011	2		(a)
		2010	2		(a)
Ameren Missouri and Genco gas	Operating Revenues	2012	1		(a)
transportation agreement		2011	1		(a)
		2010	1		(a)
Ameren Missouri and Ameren Illinois	Operating Revenues	2012	19		1
rent and facility services		2011	16		1
		2010	16		1
Ameren Illinois transmission services agreement	Operating Revenues	2012	(a)		15
with Marketing Company		2011	(a)		10
		2010	(a)		10
Total Operating Revenues		2012	$	20	$	16
		2011	19		11
		2010	19		11
Ameren Illinois power supply agreements	Purchased Power	2012	$(a)		$	311
with Marketing Company		2011	(a)		232
		2010	(a)		233
Ameren Illinois power supply	Purchased Power	2012	(a)		(b)
agreements with Ameren Missouri		2011	(a)		2
		2010	(a)		2
Total Purchased Power		2012	$(a)		$	311
		2011	(a)		234
		2010	(a)		235
Gas purchases from Genco	Gas Purchased for Resale	2012	$(a)		$	—
		2011	(a)		—
		2010	(a)		1
Ameren Services support services	Other Operations and	2012	$	106	$	88
agreement	Maintenance	2011	114		87
		2010	128		102
AFS support services agreement	Other Operations and	2012	(a)		(a)
	Maintenance	2011	(a)		(a)
		2010	7		(b)
Insurance premiums^(c)	Other Operations and	2012	(b)		(a)
	Maintenance	2011	(b)		(a)
		2010	1		(a)
Total Other Operations and		2012	$	106	$	88
Maintenance Expenses		2011	114		87
		2010	136		102
Money pool borrowings (advances)	Interest (Charges)	2012	$(b)		$(b)
	Income	2011	—		—
		2010	—		—


(a)	Not applicable.


(b)	Amount less than $1 million.


(c)	Represents insurance premiums paid to Energy Risk Assurance Company, an affiliate for replacement power, property damage, and terrorism coverage.