Legislative Decree 43 of March 14, 2025has overhauled the Testo Unico delle Accise (TUA, D.Lgs. 504/1995), Italy's consolidated excise code. For power plant operators, the operational changes take effect on January 1, 2026 and are spelled out in the DM 10 March 2026 (Official Gazette no. 66, 20/03/2026). In short: AD-1 declarations shift from annual to semi-annual filing (deadlines: end of September for H1, end of March for H2); the fixed advance-payment system gives way to monthly payments on actual quantities consumed or invoiced in the prior month; the security bond is set at 15% of estimated annual excise; and a new Accredited Operator (SOAC) status delivers bond reductions of up to 100%. The 20 kW exemption threshold for renewable-source production stays in place. For an end-to-end view of the obligation this reform rewrites, see our main guide to AD-1 filing.

Quick definitions

D.Lgs. 43/2025: Italian Legislative Decree of March 14, 2025 that reformed the Testo Unico delle Accise (D.Lgs. 504/1995); in force from January 1, 2026.
Semi-annual declaration: New AD-1 filing cadence: H1 due September 30, H2 due March 31 of the following year; replaces the single annual return.
Monthly payment: Excise paid on the prior month's actual quantities, due by the end of each month; replaces fixed advance installments.
15% bond: Surety equal to 15% of estimated annual excise, posted with the Italian Customs Agency (ADM) and updated quarterly (DM 10 March 2026, Art. 10).
SOAC-GE: Accredited Operator status for gas and electricity (Art. 9-ter to Art. 9-octies TUA); three tiers with bond reductions of 30%, 50%, and 100%.
Art. 56-ter TUA: Provision in the consolidated excise code that delegates implementation detail to the Ministerial Decree of March 10, 2026.
Sellers' monthly report: Mandatory monthly electronic transmission of invoiced quantities by use type and territorial scope (Art. 11 DM 10/03/2026), from April 1, 2026.

Update, DM 10 March 2026. The implementing decree was published on March 20, 2026 in Gazzetta Ufficialeno. 66. For an article-by-article walkthrough (plant notice, monthly advance payments, semi-annual AD-1, 15% bond, monthly sellers' reports), see DM 10 March 2026: Italy's Electricity Excise Implementing Decree.

Why this reform matters

Reform 43/2025 is the biggest shake-up of Italian electricity excise since the TUA was first enacted in 1995. The timing of obligations changes, the payment calculation method changes, and the formal categories of obligated operators change. Anyone operating a power plant - whether a commercial photovoltaic plant, a renewable energy community (CER), or a self-producer - must revise their internal processes before the first semi-annual deadline on September 30, 2026. Power plant operators are the primary audience of the reform.

Change 1: Semi-annual instead of annual declarations

The AD-1 declaration used to be annual: one document covered the whole calendar year and was due to the ADM by March 31 of the following year. From 2026, every power plant files two declarations per year:

Half-year	Reference period	Deadline
H1 2026	01/01/2026 - 30/06/2026	30/09/2026
H2 2026	01/07/2026 - 31/12/2026	31/03/2027

Filing volume doubles. The H1 deadline lands in mid-summer, so operators without automated reminders risk missing it. In practice, you need a meter reading on June 30 every year to close the first half-year, on top of the usual year-end reading.

Change 2: Monthly payments on actual quantities

This is the most operationally significant change. Before the reform, obligated operators paid fixed monthly advance installmentsbased on the prior year's tax liability, with a year-end true-up. The new system flips that: each month, excise is paid on actual quantities from the prior month:

Sellers: excise on quantities invoiced to end consumers in the prior calendar month, by supply territory.
Self-consumers (power plants with own-use consumption): excise on quantities consumed for own use in the prior month.
Seller-self-consumers: the sum of both criteria above.

Payment is due by the end of the reference month (no longer by the 16th of the following month, as under the old method). For January 2026 a transitional rule applies: the advance payment equals the December 2025 installment calculated under the old method. In practice, Quadro P (advance payments) in the AD-1 form becomes obsolete: there are no advance payments left to declare, because the monthly payment is already based on real data.

Change 3: Bond equal to 15% of estimated annual excise

The security bond (the surety posted with the ADM) is redefined by DM 10 March 2026 (Art. 10): it must equal 15% of estimated annual excise, computed from the data in the plant notice. It is then recalculated each quarter.

For operators already active on December 31, 2025, the bond adjustment takes effect on April 1, 2026 (Art. 22(1) DM 10/03/2026). You may need to renegotiate with your bank or insurer if the existing bond was sized under the old method.

Change 4: Accredited Operator status (SOAC)

D.Lgs. 43/2025 introduces, in Art. 9-ter to Art. 9-octies TUA, the status of Accredited Operator (SOAC): a trusted operator with simplified procedures and bond reductions. For electricity and natural gas, the designation is SOAC-GE. There are three reliability tiers:

Tier	Bond reduction	Notes
Basic	30%	-
Intermediate	50%	-
Extended	100%	May request a bond waiver and a single annual declaration

The decree governing SOAC accreditation procedures (Art. 9-octies TUA) had not been published as of early 2026. Until it takes effect, the SOAC system is not yet operational.

What stays unchanged

Exemption threshold: 20 kW nominal power for renewable-source production. Photovoltaic, hydro, and wind installations below this threshold whose energy is consumed by the producer remain exempt from excise and do not need to file an AD-1.
Excise rates: National rates and the regional surcharge are untouched by the reform. The rates under Art. 52 TUA stay the same.
Submission channels: S2S (System to System) and U2S (User to System) remain the two electronic channels for filing with the ADM.
Penalties: The penalty regime (Art. 50 to Art. 59 TUA) sees no material changes. Failure to file is penalized at 100% to 200% of the tax due, with a minimum of €500.

Practical checklist for power plant operators

The first semi-annual deadline is September 30, 2026 (H1 2026). Recommended steps:

Review your declarant category under the updated Art. 52 to Art. 54 TUA. Plant type, rated power, energy use, and the presence of storage (BESS) or RIU determine which AD-1 quadri are mandatory.
Renegotiate the security bond with your bank or insurer and adjust it to 15% of estimated annual excise (if you have not already done so by April 2026).
Set up monthly consumption tracking: monthly payments require knowing monthly consumed (or invoiced) quantities. An annual meter reading is no longer enough.
Schedule a meter reading for June 30, 2026 to close out the H1 data.
Update or replace your compliance software with a tool that supports the semi-annual structure, monthly payments, and the new ADM technical specifications.
Set automatic reminders for the two recurring deadlines: September 30 (H1) and March 31 (H2).

Legal sources

D.Lgs. 43 of March 14, 2025 - Testo Unico Accise reform
ADM Circular 13/2025 (June 13, 2025) - first operational guidance
ADM Circular 32/2025 (December 2025) - new use types, AD-1/AD-2 2025 guidance, 15% bond
ADM Circular 34/2025 (December 2025) - 2025 declaration filing instructions
DM 10 March 2026 - Official Gazette Serie Generale no. 66, 20/03/2026 (Prot. 26A01335)
Det. ADM 213396 of April 8, 2026 - updated monthly report templates

D.Lgs. 43/2025: Complete Guide to Italy's Electricity Excise Reform 2026