Included in SCE's regulatory assets and liabilities are regulatory balancing accounts. CPUC-authorized balancing account mechanisms require SCE to refund or recover any differences between forecasted and actual costs. The CPUC has authorized balancing accounts for specified costs or programs such as fuel, purchased power, demand-side management programs, wildfire related costs, nuclear decommissioning and public purpose programs. Certain of these

balancing accounts include a return on rate base of 7.68% in both 2021 and 2020, respectively. The CPUC authorizes the use of a balancing account to recover from or refund to customers differences in revenue resulting from actual and forecasted electricity sales.

Amounts included in regulatory assets and liabilities are generally recorded with corresponding offsets to the applicable income statement accounts.

In accordance with the accounting standards applicable to rate-regulated enterprises, SCE defers costs as regulatory assets that are probable of future recovery from customers and has recorded regulatory assets for these incremental costs at December 31, 2021. While SCE believes such costs are probable of future recovery, there is no assurance that SCE will collect all amounts currently deferred as regulatory assets.

SCE's regulatory assets related to power contracts primarily represent derivative contracts that were designated as normal purchases and normal sales contracts. The liabilities for these power contracts are amortized over the remaining contract terms, approximately 2 to 5 years. For further information, see Note 1.

SCE's regulatory assets related to deferred income taxes represent tax benefits passed through to customers. The CPUC requires SCE to flow through certain deferred income tax benefits to customers by reducing electricity rates, thereby deferring recovery of such amounts to future periods. Based on current regulatory ratemaking and income tax laws, SCE expects to recover its regulatory assets related to deferred income taxes over the life of the assets that give rise to the accumulated deferred income taxes, approximately from 1 to 60 years. For further information, see Note 8.

SCE has long-term unamortized investments which include nuclear assets related to Palo Verde and the beyond the meter program. Nuclear assets related to Palo Verde and the beyond the meter program are expected to be recovered by 2046 and 2031, respectively, and both earned returns of 7.68% in 2021 and 2020.

SCE's net regulatory asset related to its unamortized loss on reacquired debt will be recovered over the original amortization period of the reacquired debt over periods ranging from 10 to 40 years or the life of the new issuance if the debt is refunded or refinanced.

SCE's regulatory assets related to environmental remediation represent a portion of the costs incurred at certain sites that SCE is allowed to recover through customer rates. See "Environmental Remediation" discussed in Note 12.

Recovery assets represent the balance associated with the AB 1054 Excluded Capital Expenditures related Recovery Properties and prudently incurred financing costs securitized in 2021 with issuance of the associated bond. The recovery period is until 2043, when the bonds and interest are paid in full. For further details, see Note 3.

SCE's regulatory liabilities related to energy derivatives are primarily an offset to unrealized gains on derivatives.

SCE's regulatory liabilities related to costs of removal represent differences between asset removal costs recorded and amounts collected in rates for those costs.

As a result of Tax Reform, SCE's deferred tax assets and liabilities were re-measured at December 31, 2017, resulting in the initial recording of regulatory liabilities. The amount was further adjusted for CPUC's final resolution in February 2019, which stated that customers are only entitled to re-measurement of deferred taxes that were included when setting rates (i.e. included in rate base), and that all other deferred tax re-measurements belong to shareholders. The regulatory liabilities are generally expected to be refunded to customers over the lives of the assets and liabilities that gave rise to the deferred taxes.

SCE's regulatory liabilities related to recoveries in excess of ARO liabilities represents the cumulative differences between ARO expenses and amounts collected in rates primarily for the decommissioning of the SCE's nuclear generation facilities. Decommissioning costs recovered through rates are primarily placed in nuclear decommissioning trusts. This regulatory liability also represents the deferral of realized and unrealized gains and losses on the nuclear decommissioning trust investments. See Note 10 for further discussion.

SCE's regulatory liabilities related to pension and other post-retirement plans represent the overfunded net gains and prior service costs of the plans. This amount will be refunded through rates over time to customers. See "Pension Plans and Postretirement Benefits Other than Pensions" discussion in Note 9.

Balancing accounts track amounts that the CPUC or FERC have authorized for recovery. Balancing account over and under collections represent differences between cash collected in current rates for specified forecasted costs and such costs that are actually incurred. Undercollections are recorded as regulatory balancing account assets. Overcollections are recorded as regulatory balancing account liabilities. With some exceptions, SCE seeks to adjust rates on an annual basis or at other designated times to recover or refund the balances recorded in its balancing accounts. Memorandum accounts are authorized to track costs for potential future recovery.

Regulatory balancing and memorandum accounts that SCE does not expect to collect or refund in the next 12 months are reflected in the long-term section of the consolidated balance sheets. Regulatory balancing and memorandum accounts that do not have the right of offset are presented gross in the consolidated balance sheets. Under and over collections in balancing accounts and amounts recorded in memorandum accounts typically accrue interest based on a three-month commercial paper rate published by the Federal Reserve.

The following table summarizes the significant components of regulatory balancing and memorandum accounts included in the above tables of regulatory assets and liabilities:

The 2021 GRC decision approved the establishment of the vegetation management balancing account ("VMBA") to track vegetation management expenses up to 115% of amounts authorized, the Wildfire Risk Mitigation balancing account ("WRMBA") to track the costs of SCE's Wildfire Covered Conductor Program up to 110% of amounts authorized and the risk management balancing account to track the authorized costs of wildfire insurance. The amount recorded to these balancing accounts represents the difference between costs tracked in the balancing accounts and authorized revenues for those costs recorded to the base revenue requirement balancing account. If spending is less than authorized, SCE will refund those amounts to customers. If spending is within the specified threshold, if any, for each balancing account, SCE will recover those costs from customers. Amounts above the specified threshold, or above amounts authorized if a higher threshold was not established, for each balancing account may be eligible for deferral to wildfire-related memorandum accounts.

2	The wildfire and drought restoration accounts regulatory assets represent restoration costs that are recorded in a Catastrophic Event Memorandum Account ("CEMA").

The wildfire-related memorandum accounts regulatory assets represent wildfire-related costs that are probable of future recovery from customers, subject to a reasonableness review. The Fire Hazard Prevention Memorandum Account ("FHPMA") was used to track costs related to fire safety and to implement fire prevention corrective action measures in extreme and very high fire threat areas. The Wildfire Expense Memorandum Account ("WEMA") is used to track incremental wildfire insurance costs and

uninsured wildfire-related financing, legal and claims costs. The Wildfire Mitigation Plan Memorandum Account ("WMPMA") is used to track costs incurred to implement SCE's wildfire mitigation plan that are not currently reflected in SCE's revenue requirements. The Fire Risk Mitigation Memorandum Account ("FRMMA") is used to track costs related to the reduction of fire risk that are incremental to costs approved for recovery in SCE's GRCs that are not tracked in any other wildfire-related memorandum account. The balance also includes vegetation management spending in excess of the 115% threshold for the VMBA described above.

CSRP memorandum account was established in the 2018 GRC to track costs for implementation of a new customer service system not currently reflected in SCE's revenue requirements. Expenditures for the CSRP project are subject to reasonableness review by the CPUC, expenditures for the project were significantly higher than originally projected.