RELATED-PARTY TRANSACTIONS

In the normal course of business, Ameren Missouri and Ameren Illinois have engaged in, and may in the future engage in, affiliate transactions. These transactions primarily consist of natural gas and power purchases and sales, services received or rendered, and borrowings and lendings. Transactions between Ameren’s subsidiaries are reported as affiliate transactions on their individual financial statements, but those transactions are eliminated in consolidation for Ameren’s consolidated financial statements. Below are the material related-party agreements.

Electric Power Supply Agreements

Ameren Illinois must acquire capacity and energy sufficient to meet its obligations to customers. Ameren Illinois uses periodic RFP processes, administered by the IPA and approved by the ICC, to contract capacity and energy on behalf of its customers. Ameren Missouri participates in the RFP process and has been a winning supplier for certain periods.

Capacity Supply Agreements

In a procurement event in 2012, Ameren Missouri contracted to supply a portion of Ameren Illinois’ capacity requirements for $3 million for the 12 months ended May 31, 2015. In a procurement event in 2015, Ameren Missouri contracted to supply a portion of Ameren Illinois’ capacity requirements for $15 million for the 12 months ending May 31, 2017.

Energy Swaps and Energy Products

Based on the outcome of IPA-administered procurement events, Ameren Missouri and Ameren Illinois have entered into energy product agreements by which Ameren Missouri agreed to sell, and Ameren Illinois agreed to purchase, a set amount of megawatthours at a predetermined price over a specified period of time. The following table presents the agreements the companies have entered into, as well as the specified performance period, price, and amount of megawatthours included in each agreement:



IPA Procurement Event	Performance Period	MWh		Average Price per MWh
May 2014	January 2015 – February 2017	168,400	$	51
April 2015	June 2015 – June 2017	667,000		36
September 2015	November 2015 – May 2018	339,000		38
April 2016	June 2017 – September 2018	375,200		35
September 2016	May 2017 – September 2018	82,800		34
April 2017	March 2019 – May 2020	85,600		34

Collateral Postings

Under the terms of the Illinois energy product agreements entered into through RFP processes administered by the IPA, suppliers must post collateral under certain market conditions to protect Ameren Illinois in the event of nonperformance. The collateral postings are unilateral, which means that only the suppliers can be required to post collateral. Therefore, Ameren Missouri, as a winning supplier in the RFP process, may be required to post collateral. As of December 31, 2017 and 2016, there were no collateral postings required of Ameren Missouri related to the Illinois energy product agreements.

Interconnection and Transmission Agreements

Ameren Missouri and Ameren Illinois are parties to an interconnection agreement for the use of their respective transmission lines and other facilities for the distribution of power. These agreements have no contractual expiration date, but may be terminated by either party with three years’ notice.

Support Services Agreements

Ameren Services provides support services to its affiliates. The costs of support services, including wages, employee benefits, professional services, and other expenses, are based on, or are an allocation of, actual costs incurred. The support services agreement can be terminated at any time by the mutual agreement of Ameren Services and that affiliate or by either party with 60 days’ notice before the end of a calendar year.

In addition, Ameren Missouri and Ameren Illinois provide affiliates, primarily Ameren Services, with access to their facilities for administrative purposes. The costs of the rent and facility services are based on, or are an allocation of, actual costs incurred.

Separately, Ameren Missouri and Ameren Illinois provide storm-related and miscellaneous support services to each other on an as-needed basis.

Transmission Services

Ameren Illinois receives transmission services from ATXI for its retail load in the AMIL pricing zone.

Money Pool

See Note 4 – Short-term Debt and Liquidity for a discussion of affiliate borrowing arrangements.

Tax Allocation Agreement

See Note 1 – Summary of Significant Accounting Policies for a discussion of the tax allocation agreement. As of December 31, 2017 and 2016, Ameren Missouri had income taxes payable to Ameren (parent) of $11 million and $16 million, respectively, included in “Accounts payable - affiliates” on its balance sheet. As of December 31, 2017 and 2016, Ameren Illinois had income taxes payable to Ameren (parent) of $17 million and $3 million, respectively, included in “Accounts payable - affiliates” on its balance sheet. See below for capital contributions received related to the tax allocation agreement.

Capital Contributions

In 2017, Ameren Missouri received cash capital contributions of $30 million from Ameren (parent) as a result of the tax allocation agreement. In 2017, Ameren Illinois received cash capital contributions of $8 million from Ameren (parent).

In 2016, Ameren Missouri received cash capital contributions of $44 million from Ameren (parent) as a result of the tax allocation agreement, which included the accrued capital contribution from 2015.

In 2015, Ameren Missouri received cash capital contributions of $224 million from Ameren (parent) as a result of the tax allocation agreement, which included the accrued capital contribution from 2014. Additionally, as of December 31, 2015, Ameren Missouri accrued a $38 million capital contribution related to the same agreement. In 2015, Ameren Illinois received cash capital contributions of $25 million from Ameren (parent).

The following table presents the impact on Ameren Missouri and Ameren Illinois of related-party transactions for the years ended December 31, 2017, 2016, and 2015. 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	2017	$	23	$	(a)
with Ameren Illinois		2016		28		(a)
		2015		15		(a)
Ameren Missouri and Ameren Illinois	Operating Revenues	2017		26		4
rent and facility services		2016		25		5
		2015		25		4
Ameren Missouri and Ameren Illinois	Operating Revenues	2017		(b)		1
miscellaneous support services		2016		1		(b)
		2015		2		(b)
Total Operating Revenues		2017	$	49	$	5
		2016		54		5
		2015		42		4
Ameren Illinois power supply	Purchased Power	2017	$	(a)	$	23
agreements with Ameren Missouri		2016		(a)		28
		2015		(a)		15
Ameren Illinois transmission	Purchased Power	2017		(a)		2
services from ATXI		2016		(a)		2
		2015		(a)		2
Total Purchased Power		2017	$	(a)	$	25
		2016		(a)		30
		2015		(a)		17
Ameren Services support services	Other Operations and	2017	$	149	$	139
agreement	Maintenance	2016		129		123
		2015		131		119
Money pool borrowings (advances)	(Interest Charges)	2017	$	1	$	(b)
	Miscellaneous Income	2016		(b)		(b)
		2015		(b)		(b)


(a)	Not applicable.


(b)	Amount less than $1 million.