From April 1, 2026, every power plant (officina elettrica) operator must post a surety bond (cauzione) with the Agenzia delle Dogane e dei Monopoli (Italian Customs Agency, ADM) equal to 15% of the estimated annual excise duty. The formula: annual kWh consumed or transferred (from the plant declaration) x applicable excise rate x 15%. DM 10 March 2026, Art. 10 sets this rule under D.Lgs. 43/2025. Operators already active on December 31, 2025 had to comply by April 1, 2026. Recalculate the bond quarterly against actual consumption. Plants with SOAC (Soggetto Obbligato Accreditato) status can cut it by 30% to 100%. The bond is one piece of the wider AD-1 filing cycle; for the full picture, see our AD-1 overview.
Quick definitions
- Surety bond (cauzione)
- Guarantee (bank guarantee or surety insurance policy) lodged with ADM to cover excise duty owed by the power plant.
- 15% formula
- Annual kWh (from plant declaration) × applicable excise rate × 15%. Source: DM 10 March 2026, Art. 10.
- Excise rate (Art. 52 TUA)
- Electricity excise rate in €/kWh; varies by use type (domestic, industrial, agricultural, public lighting).
- Quarterly update
- Bond recalculation required when actual quarterly consumption deviates by 20% or more from the estimate (Art. 10, c.3).
- SOAC-GE
- Accredited Operator status for gas and electricity (Arts. 9-ter to 9-octies TUA); Basic, Intermediate, and Advanced tiers cut the bond by 30%, 50%, and 100%.
- Art. 22, c.1
- Transitional provision of DM 10/03/2026: April 1, 2026 deadline to adjust bonds for operators already active on 31/12/2025.
- Plant declaration (denuncia)
- Document filed with ADM's Ufficio Tecnico di Finanza listing identification data and estimated annual consumption and production figures for the plant.
What is the surety bond for power plants
The surety bond (cauzione) is a guarantee, typically a bank guarantee (fideiussione bancaria) or a surety insurance policy (polizza assicurativa cauzionale), that the power plant operator provides to ADM as a condition for the operating authorization. It covers the excise duty owed if the operator becomes insolvent. It is not a cash deposit with ADM: the document stays with the bank or insurance company while the plant is active, but ADM can call on it on default.
Before the D.Lgs. 43/2025 reform, the bond amount followed different criteria, often tied to fixed annual installments. The reform unifies the method with a single formula that applies to all declarant categories and updates quarterly.
The new formula: 15% of estimated annual excise duty
Multiply the annual kWh declared in the plant declaration by the applicable excise rate, then apply 15%:
| Parameter | Example: industrial plant |
|---|---|
| Annual kWh (from plant declaration) | 500,000 kWh |
| Rate, industrial use (Art. 52 TUA) | €0.0125/kWh |
| Estimated annual excise duty | €6,250 |
| Surety bond (15%) | €938 |
The applicable rate depends on the intended use and the declarant category: domestic use (€0.0227/kWh), public lighting, industrial use, agricultural use, and so on. Plants with mixed uses apply a weighted average of the relevant rates.
Quarterly bond update
The bond is not fixed for the whole operating period. DM 10 March 2026, Art. 10, c.3 requires quarterly updates based on a 20% variation threshold:
- If actual quarterly consumption exceeds the pro-rata annual estimate by 20% or more, the operator must increase the bond by the end of the month following the reference quarter.
- If consumption falls 20% or more below the estimate, the operator can request a reduction by the same deadline.
- Variations under 20% do not trigger an immediate update; recalibration happens at the next plant declaration.
Who is affected
The surety bond requirement applies to liable parties under Arts. 52-54 TUA as updated by D.Lgs. 43/2025:
- Holders of an operating license (Art. 53, c.1 TUA): plants above 20 kW that supply energy to third parties
- Holders of an own-use authorization (Art. 53, c.5 TUA): plants above 20 kW with full or partial self-consumption
- Renewable Energy Communities (CER) that produce and share energy
- Internal Distribution Networks (RIU, Reti Interne d'Utenza)
- Entities filing a simple notification (Art. 53, c.3 TUA), including renewable producers between 20 kW and 200 kW that inject into the grid
The bond does not apply to producers with nominal power under 20 kW (the excise exemption threshold, Art. 52, c.1 TUA) or to entities classified as non-liable.
Transitional rules: operators already active on 31/12/2025
Art. 22, c.1 of DM 10/03/2026 sets April 1, 2026 as the deadline to adjust the bond to the new formula for operators who already held an authorization on December 31, 2025. No official extensions have followed that date.
Compliance requires:
- Calculate the new bond: kWh from plant declaration x applicable rate x 15%
- Contact the bank or insurance company to amend the existing guarantee or issue a new document for the calculated amount
- Deliver the updated document to the ADM Ufficio Tecnico di Finanza that covers the plant's territory
SOAC status and bond reduction
SOAC-GE status (Soggetto Obbligato Accreditato), introduced by Arts. 9-ter to 9-octies TUA, unlocks meaningful cuts to the bond:
| SOAC Level | Bond reduction |
|---|---|
| Basic | 30% |
| Intermediate | 50% |
| Advanced | 100% (full exemption) |
The implementing decree that governs SOAC accreditation procedures had not been published as of early 2026; until it takes effect, SOAC status is not operational. For more on the overall reform, see D.Lgs. 43/2025 reform guide.
How to comply: bank or insurance
- Calculate the estimated annual excise duty: multiply the kWh declared in the plant declaration by the rate that applies to your intended use.
- Apply 15%: that is the bond amount to post.
- Contact the bank or insurance company: request a bank guarantee or surety insurance policy for the calculated amount, made out to the Agenzia delle Dogane e dei Monopoli.
- Submit the document to ADM: deliver it to the ADM Ufficio Tecnico di Finanza that covers the plant's territory.
- Plan the quarterly update: set a reminder every three months to compare actual consumption with the estimate and check whether the variation passes 20%.
Legal sources
- D.Lgs. 14 March 2025, n. 43: reform of the Testo Unico delle Accise (D.Lgs. 504/1995)
- DM 10 March 2026, Art. 10: surety bond for power plants, formula and update
- DM 10 March 2026, Art. 22, c.1: transitional deadline April 1, 2026
- ADM Circular 32/2025: initial guidance on the 15% bond
- Arts. 52 and 53 TUA: excise rates and liable parties
Deklara calculates the surety bond automatically from the plant declaration and alerts you when a quarterly update is due.
Further reading
- Complete Guide to the AD-1 Declaration - pillar reference on quadri, deadlines, and excise duty calculation.
- D.Lgs. 43/2025: What Changes for AD-1 Declarations in 2026 - the reform that introduced the 15% rule.
- DM 10 March 2026: Italy's Electricity Excise Implementing Decree - the implementing decree (Art. 10) behind the bond formula.
- Italian Power Plant: Declarant Categories, ADM Licenses and Filing Obligations - which declarant categories must post a bond.