v3.25.1
RELATED PARTY TRANSACTIONS (Tables)
3 Months Ended
Mar. 31, 2025
Related Party Transactions [Abstract]  
Schedule of Related Party Balances and Transactions
The following table presents the components of related party balances included in Accounts Receivable, Net and Accounts Payable on the Condensed Consolidated Balance Sheets:
(in millions)March 31, 2025December 31, 2024
Receivables from Related Parties
UNS Energy$$
UNS Electric
UNS Gas
Total Due from Related Parties$15 $10 
Payables to Related Parties
UNS Energy$$
UNS Electric
Total Due to Related Parties$$
The following table presents the components of related party transactions included on the Condensed Consolidated Statements of Income:
Three Months Ended March 31,
(in millions)20252024
Goods and Services Provided by TEP to Affiliates
Common Costs, UNS Energy Affiliates (1)
$$
Transmission Revenues, UNS Electric (2)
Wholesale Revenues, UNS Electric (2)
Goods and Services Provided by Affiliates to TEP
Corporate Services, UNS Energy (3)
$$
Capacity Charges, UNS Gas (4)
Purchased Power, UNS Electric (2)
— 
(1)Common costs (information systems, facilities, etc.) are allocated on a cost-causative basis and recorded as revenue by TEP. The method of allocation is deemed reasonable by management and is reviewed by the ACC as part of the rate case process.
(2)TEP and UNS Electric sell power to each other, and TEP sells transmission services to UNS Electric. Wholesale power is sold at prevailing market prices, while transmission services are sold at FERC-approved rates through the applicable Open Access Transmission Tariff.
(3)Corporate Services, UNS Energy includes legal and audit, and Fortis' management fees. Costs for corporate services provided by UNS Energy are allocated to its subsidiaries using the Massachusetts Formula, an industry accepted method of allocating common costs to affiliated entities. TEP's allocation is approximately 84% of UNS Energy's allocated costs. TEP's share of Fortis' management fees was $3 million and $2 million for the three months ended March 31, 2025, and 2024, respectively.
(4)UNS Gas charges TEP for natural gas capacity used to supply Gila River Generating Station.