SDI Sending Invoices Guide

Generate and issue electronic invoices through Italy’s SDI system

Introduction

Electronic invoicing is mandatory for all businesses in Italy. The Sistema di Interscambio (SDI) serves as the Italian government’s central hub for transmitting, validating, and delivering all electronic invoices throughout the country.

The SDI system operates using a standardized XML format called FatturaPA, which ensures all invoices contain the required information and comply with the strict validation rules established by the Italian tax authority (Agenzia delle Entrate). To ensure proper routing of invoices to the correct recipient, the SDI system uses a unique identifier called a Recipient Code, which is assigned to each registered SDI provider.

Invopop simplifies SDI integration by allowing you to work with GOBL format instead of XML, providing synchronous validation before submission, and offering a simple API integration with automatic handling of SDI notifications and status updates. For receiving invoices through SDI, see our companion guide: Italy - SDI: Receiving Invoices.

Setup

1. Connect the SDI Italy app

   1. Navigate to Configuration → Apps
   2. Locate SDI Italy in the app discovery list
   3. Tap Connect to activate

   

   The initial connection requires no configuration for sending invoices.

2. Configure sending workflow

   SDI does not have a sandbox environment. When sandbox mode is selected, Invopop’s third-party submission service, A-Cube, simulates a response from SDI.

   Template

   SDI send invoice workflow

   Signs and converts the

   GOBL document into the FatturaPA XML format and then sends it to SDI.

   Add to my workspace

   Code

   Copy and paste into a new Empty Invoice workflow code view.

   Example SDI send invoice workflow with states

   {
     "name": "SDI send invoice",
     "description": "Generate and issue an invoice through SDI",
     "schema": "bill/invoice",
     "steps": [
       {
         "id": "1a692ae0-cd12-11ef-998c-e97f18c9212e",
         "name": "Set State",
         "provider": "silo.state",
         "summary": "Set state to `processing`{.state .processing}",
         "config": {
           "state": "processing"
         }
       },
       {
         "id": "1855b430-cd12-11ef-998c-e97f18c9212e",
         "name": "Sign Envelope",
         "provider": "silo.close"
       },
       {
         "id": "2042f860-cd12-11ef-998c-e97f18c9212e",
         "name": "Send to SDI (Italy)",
         "provider": "sdi-it.send",
         "summary": "Sandbox · Accepted by PA (Notifica esito)",
         "config": {
           "environment": "sandbox",
           "response": "NE"
         }
       },
       {
         "id": "236965b0-cd12-11ef-998c-e97f18c9212e",
         "name": "Generate PDF",
         "provider": "pdf",
         "summary": "Italian",
         "config": {
           "date_format": "%Y-%m-%d",
           "locale": "it",
           "logo_height": 40
         }
       },
       {
         "id": "2b6db450-cd12-11ef-998c-e97f18c9212e",
         "name": "Set State",
         "provider": "silo.state",
         "summary": "Set state to `sent`{.state .sent}",
         "config": {
           "state": "sent"
         }
       }
     ],
     "rescue": [
       {
         "id": "2d5d7660-cd12-11ef-998c-e97f18c9212e",
         "name": "Set State",
         "provider": "silo.state",
         "summary": "Set state to `error`{.state .error}",
         "config": {
           "state": "error"
         }
       }
     ]
   }
   
   

   Build from scratch

   Before starting, review the workflows guide to understand the general setup process.

   In Console, create a new workflow and choose Empty Invoice workflow as the base. Then add the following steps:

   1. Set State - To Processing.
   2. Sign Envelope - Signs the GOBL document preventing further modifications.
   3. Send to SDI (Italy) - Generates the FatturaPA XML and sends it to SDI. Upon success, the XML file is attached to the invoice entry. If sandbox is chosen as the environment, the simulated response from SDI must be set.
   4. Set State - To Sent.

   In the Error Handling section, add a Set State step with the state set to Error to capture and flag failed imports.

   This is the minimal workflow with state handling required to automate the reception and visualization of invoices received through SDI. You may expand it with additional steps such as storing a backup copy, notifying clients, or integrating the documents into an ERP system.

   

Sending Invoices

Invopop uses the GOBL FatturaPA library to process conversions. When creating invoices for SDI, you need to:

1. Set the regime field to IT in your GOBL invoice
2. Add the it-sdi-v1 addon to enable Italian-specific validations and extensions

Detailed information about the SDI-specific extensions and validations can be found in:

• Italy SDI FatturaPA v1.x Addon Documentation
• Italy Tax Regime Documentation

Example invoices are provided below, or you can use the GOBL Builder to create custom invoices.

How the Send step works

This step generates the FatturaPA XML and sends it to SDI through our integration partner. Upon successful completion, the XML file is attached to the invoice entry. The SDI service usually responds within seconds but may take up to 24 hours. While waiting, this step remains in a Queued state.

When the Send step completes, it returns one of three results:

• OK if successful
• KO for unrecoverable errors
• SKIP if the invoice was already sent

Example Invoices

B2C Standard Invoice

In this example, we’re issuing a standard B2C invoice from an Italian supplier to a consumer.

Notice:

• the minimal version (sdi-b2c.min.mdx) contains only the essential fields required to create the invoice,
• the it-sdi-v1 addon ensures the document will be validated using the SDI (Sistema di Interscambio) rules built into the GOBL library,
• customer details may be simplified for B2C transactions as per Italian requirements,
• there are no totals or calculations in the minimal version; all these will be calculated automatically when running gobl build,
• the built version (sdi-b2c.mdx) shows the normalized document with calculated totals, line item sums, IVA (VAT) breakdowns, and automatically generated fields, and,
• make sure to process it with the SDI workflow to transmit the invoice to the Italian tax authority.

SDI B2C Invoice

{
  "$schema": "https://gobl.org/draft-0/bill/invoice",
  "$regime": "IT",
  "$addons": [
    "it-sdi-v1"
  ],
  "series": "FT",
  "code": "020",
  "issue_date": "2024-07-12",
  "currency": "EUR",
  "tax": {
    "prices_include": "VAT"
  },
  "supplier": {
    "name": "Company Name S.r.l.",
    "tax_id": {
      "country": "IT",
      "code": "12345678903"
    },
    "addresses": [
      {
        "num": "102",
        "street": "Via California",
        "locality": "Palermo",
        "region": "PA",
        "code": "33213",
        "country": "IT"
      }
    ],
    "registration": {
      "capital": "50000.00",
      "currency": "EUR",
      "office": "RM",
      "entry": "123456"
    },
    "ext": {
      "it-sdi-fiscal-regime": "RF01"
    }
  },
  "customer": {
    "name": "Customer Name S.r.l.",
    "tax_id": {
      "country": "IT"
    },
    "identities": [
      {
        "key": "it-fiscal-code",
        "code": "RSSGNN60R30H501U"
      }
    ],
    "addresses": [
      {
        "num": "23",
        "street": "Via dei Mille",
        "locality": "Firenze",
        "region": "FI",
        "code": "00100",
        "country": "IT"
      }
    ]
  },
  "lines": [
    {
      "quantity": "1",
      "item": {
        "name": "Cleaning services",
        "price": "125.00"
      },
      "taxes": [
        {
          "cat": "VAT",
          "rate": "standard"
        }
      ]
    }
  ]
}

B2B Invoice

In this example, we’re issuing a standard B2B invoice from an Italian supplier to another Italian business customer.

Notice:

• both supplier and customer have their Partita IVA (VAT number) and Codice Fiscale properly specified,
• the minimal version contains only essential fields; gobl build handles all calculations,
• when running gobl build, the system automatically calculates totals, applies IVA rates, and normalizes the document according to SDI requirements,
• the built version shows all calculated fields including tax breakdowns, line totals, payment terms, and final amounts,
• the it-sdi-v1 addon validates the document structure for B2B transactions, and,
• the invoice will be transmitted through the SDI system and delivered to the customer’s designated channel.

SDI B2B Invoice

{
  "$schema": "https://gobl.org/draft-0/bill/invoice",
  "$regime": "IT",
  "$addons": [
    "it-sdi-v1"
  ],
  "series": "SAMPLE",
  "code": "002",
  "issue_date": "2023-05-21",
  "currency": "EUR",
  "tax": {
    "prices_include": "VAT"
  },
  "supplier": {
    "name": "Hotel California",
    "tax_id": {
      "country": "IT",
      "code": "12345678903"
    },
    "addresses": [
      {
        "num": "102",
        "street": "Via California",
        "locality": "Palermo",
        "region": "PA",
        "code": "33213",
        "country": "IT"
      }
    ],
    "registration": {
      "capital": "50000.00",
      "currency": "EUR",
      "office": "RM",
      "entry": "123456"
    },
    "ext": {
      "it-sdi-fiscal-regime": "RF01"
    }
  },
  "customer": {
    "name": "Mela S.r.l.",
    "tax_id": {
      "country": "IT",
      "code": "13029381004"
    },
    "inboxes": [
      {
        "key": "it-sdi-code",
        "code": "M5UXCR5"
      }
    ],
    "addresses": [
      {
        "num": "23",
        "street": "Via dei Mille",
        "locality": "Firenze",
        "region": "FI",
        "code": "00100",
        "country": "IT"
      }
    ]
  },
  "lines": [
    {
      "quantity": "1",
      "item": {
        "name": "Tassa di Soggiorno",
        "price": "1.00"
      },
      "taxes": [
        {
          "cat": "VAT",
          "rate": "exempt",
          "ext": {
            "it-sdi-exempt": "N4"
          }
        }
      ]
    },
    {
      "quantity": "1",
      "item": {
        "name": "Camera Matrimoniale",
        "price": "125.00"
      },
      "taxes": [
        {
          "cat": "VAT",
          "rate": "intermediate"
        }
      ]
    }
  ]
}

B2B Invoice with Additional Fields

In this example, we’re issuing a comprehensive B2B invoice with additional optional fields such as ordering information, payment details, and document references.

Notice:

• this invoice demonstrates advanced SDI features like CIG/CUP codes, payment methods, and bank details,
• the minimal version includes ordering and payment details; gobl build calculates all totals,
• when running gobl build, the system validates all additional fields according to SDI specifications and calculates totals,
• the built version shows the complete document with all calculated fields, tax breakdowns, and properly formatted additional information,
• additional fields like ordering, payment, and document references are important for public administration invoices (B2G), and,
• the addon ensures all optional fields are properly validated and formatted for SDI transmission.

SDI B2B Invoice with additional fields

{
  "$schema": "https://gobl.org/draft-0/bill/invoice",
  "$regime": "IT",
  "$addons": [
    "it-sdi-v1"
  ],
  "$tags": [
    "freelance"
  ],
  "series": "SAMPLE",
  "code": "001",
  "issue_date": "2023-03-02",
  "currency": "EUR",
  "supplier": {
    "name": "MªF. Services",
    "tax_id": {
      "country": "IT",
      "code": "12345678903"
    },
    "people": [
      {
        "name": {
          "given": "GIANCARLO",
          "surname": "ROSSI"
        }
      }
    ],
    "addresses": [
      {
        "num": "1",
        "street": "VIALE DELLA LIBERTÀ",
        "locality": "ROMA",
        "region": "RM",
        "code": "00100",
        "country": "IT"
      }
    ],
    "emails": [
      {
        "addr": "[e-mail]"
      }
    ],
    "telephones": [
      {
        "num": "999999999"
      }
    ],
    "registration": {
      "capital": "50000.00",
      "currency": "EUR",
      "office": "RM",
      "entry": "123456"
    },
    "ext": {
      "it-sdi-fiscal-regime": "RF02"
    }
  },
  "customer": {
    "name": "MARIO LEONI",
    "tax_id": {
      "country": "IT",
      "code": "09876543217"
    },
    "people": [
      {
        "name": {
          "prefix": "Dott.",
          "given": "MARIO",
          "surname": "LEONI"
        }
      }
    ],
    "inboxes": [
      {
        "key": "it-sdi-code",
        "code": "M5UXCR5"
      }
    ],
    "addresses": [
      {
        "num": "1",
        "street": "VIALE DELI LAVORATORI",
        "locality": "ROMA",
        "region": "RM",
        "code": "00100",
        "country": "IT"
      }
    ],
    "emails": [
      {
        "addr": "[e-mail]"
      }
    ]
  },
  "lines": [
    {
      "quantity": "20",
      "item": {
        "name": "Development of accounting software",
        "price": "10.00",
        "unit": "h"
      },
      "taxes": [
        {
          "cat": "VAT",
          "rate": "standard"
        }
      ]
    }
  ],
  "payment": {
    "instructions": {
      "key": "credit-transfer",
      "credit_transfer": [
        {
          "iban": "IT60X0542811101000000123456",
          "name": "MªF. Services"
        }
      ]
    },
    "terms": {
      "due_dates": [
        {
          "date": "2023-09-01",
          "percent": "100%"
        }
      ]
    }
  }
}

VAT Exempt Invoice

In this example, we’re issuing an invoice for goods or services that are exempt from VAT (IVA).

Notice:

• the line item includes a tax with "key": "exempt" indicating this is a VAT-exempt transaction,
• the minimal version omits the exemption code extension (it-sdi-exempt), which will be automatically added during gobl build,
• when running gobl build, the system calculates totals with zero VAT and validates the exemption structure,
• the built version shows the complete document with the exemption code extension (e.g., "it-sdi-exempt": "N4") applied to the tax rate,
• exemption codes must comply with SDI requirements—consult the complete list of exemption reasons in the GOBL documentation,
• common exemption codes include N4 (exempt), N3.1 (exports), N3.2 (intra-community supplies), and N6.x (reverse charge scenarios), and,
• the SDI validates that exempt invoices include proper exemption codes before transmission.

SDI Exempt Invoice

{
    "$schema": "https://gobl.org/draft-0/bill/invoice",
    "$regime": "IT",
    "$addons": [
        "it-sdi-v1"
    ],
    "code": "INVOICE-001",
    "supplier": {
        "name": "Example IT Supplier S.r.l.",
        "tax_id": {
            "country": "IT",
            "code": "12345678903"
        },
        "addresses": [
            {
                "street": "Via Roma, 123",
                "locality": "Milan",
                "code": "20121",
                "country": "IT"
            }
        ],
        "emails": [
            {
                "addr": "[e-mail]"
            }
        ]
    },
    "customer": {
        "name": "Example IT Customer S.p.A.",
        "tax_id": {
            "country": "IT",
            "code": "13029381004"
        },
        "addresses": [
            {
                "street": "Via Dante, 456",
                "locality": "Rome",
                "code": "00100",
                "country": "IT"
            }
        ]
    },
    "lines": [
        {
            "quantity": "10",
            "item": {
                "name": "Tax Exempt Service",
                "price": "100.00"
            },
            "taxes": [
                {
                    "cat": "VAT",
                    "key": "exempt"
                }
            ]
        }
    ]
}

Credit Note

In this example, we’re issuing a credit note (nota di credito) to correct or refund a previously issued invoice.

Notice:

• the type field is set to credit-note to indicate this is a corrective document,
• the preceding field references the original invoice being corrected,
• the minimal version contains only essential correction details; gobl build calculates negative amounts,
• when running gobl build, the system automatically calculates negative totals, IVA refunds, validates the credit note structure, and applies SDI rules,
• the built version shows all calculated fields including negative amounts for the refund and proper tax adjustments,
• credit notes must be properly linked to the original invoice and transmitted through SDI, and,
• the SDI system validates the credit note format before accepting and forwarding it to the recipient.

SDI Credit Note

{
  "$schema": "https://gobl.org/draft-0/bill/invoice",
  "$regime": "IT",
  "$addons": [
    "it-sdi-v1"
  ],
  "$tags": [
    "freelance"
  ],
  "type": "credit-note",
  "series": "CN",
  "code": "001",
  "issue_date": "2024-10-09",
  "currency": "EUR",
  "preceding": [
    {
      "uuid": "0190c0ec-8109-756b-a4f0-88c4b542ab6e",
      "type": "standard",
      "issue_date": "2023-03-02",
      "series": "SAMPLE",
      "code": "001"
    }
  ],
  "supplier": {
    "name": "MªF. Services",
    "tax_id": {
      "country": "IT",
      "code": "12345678903"
    },
    "people": [
      {
        "name": {
          "given": "GIANCARLO",
          "surname": "ROSSI"
        }
      }
    ],
    "addresses": [
      {
        "num": "1",
        "street": "VIALE DELLA LIBERTÀ",
        "locality": "ROMA",
        "region": "RM",
        "code": "00100",
        "country": "IT"
      }
    ],
    "registration": {
      "capital": "50000.00",
      "currency": "EUR",
      "office": "RM",
      "entry": "123456"
    },
    "ext": {
      "it-sdi-fiscal-regime": "RF02"
    }
  },
  "customer": {
    "name": "MARIO LEONI",
    "tax_id": {
      "country": "IT",
      "code": "09876543217"
    },
    "people": [
      {
        "name": {
          "prefix": "Dott.",
          "given": "MARIO",
          "surname": "LEONI"
        }
      }
    ],
    "inboxes": [
      {
        "key": "it-sdi-code",
        "code": "M5UXCR5"
      }
    ],
    "addresses": [
      {
        "num": "1",
        "street": "VIALE DELI LAVORATORI",
        "locality": "ROMA",
        "region": "RM",
        "code": "00100",
        "country": "IT"
      }
    ],
    "emails": [
      {
        "addr": "[e-mail]"
      }
    ]
  },
  "lines": [
    {
      "quantity": "20",
      "item": {
        "name": "Development of accounting software",
        "price": "10.00",
        "unit": "h"
      },
      "taxes": [
        {
          "cat": "VAT",
          "rate": "standard"
        }
      ]
    }
  ],
  "payment": {
    "instructions": {
      "key": "credit-transfer",
      "credit_transfer": [
        {
          "iban": "IT60X0542811101000000123456",
          "name": "MªF. Services"
        }
      ]
    }
  }
}

Technical Details

SDI Response Codes and Statuses

When the SDI step processes a document, it returns detailed status codes that provide information about the response from SDI:

Code	Description
rejected	Notifica di scarto (NS) SDI has rejected the invoice because it contains errors.
delivered	Ricevuta consegna (RC) SDI has successfully delivered a B2B invoice to the recipient.
delivered-pa	Ricevuta consegna (RC) SDI has successfully delivered an invoice to a Public Administration (PA).
not-delivered	Mancata consegna (MC) SDI could not deliver the invoice to the recipient.
not-delivered	Attestazione trasmissione con impossibilità di recapito (AT) SDI couldn’t deliver an invoice to PA after 10 days.
accepted-pa	Notifica esito (NE) A PA has decided to accept an invoice (outcome EC01).
rejected-pa	Notifica esito (NE) A PA has decided to reject an invoice (outcome EC02).
deadline-terms	Notifica decorrenza termini (DT) A PA didn’t reply with acceptance or rejection within 15 days.
invoice-error	An error occurred during the acquisition of a notification.
sent	The invoice has been submitted to SDI and is awaiting a response.
not-received	The invoice was not received by the recipient.

Some SDI notifications (File metadati - MT, Esito committente - EC, Scarto esito committente - SE) don’t directly change the code of the invoice.

These codes map to different step results as follows:

• OK Result: delivered, not-delivered, not-received, accepted-pa
• KO Result: rejected, rejected-pa, invoice-error, deadline-terms
• QUEUED Result: sent, delivered-pa

When a step returns QUEUED, the workflow will check again later for updates from SDI.

---

🇮🇹 Invopop resources for Italy

Compliance	Invoicing compliance in Italy Compliance timeline
Apps	SDI Italy Smart Receipts Italy
Guides	SDI Sending Guide SDI Receiving Guide Ticket Guide
FAQ	Italy FAQ
GOBL	Italy Tax Regime Italy SDI FatturaPA Addon Italy AdE Ticket Addon
GitHub	gobl.fatturapa

Italy FAQ

Find answers to frequently asked questions about invoicing in Italy →

Participate in our community

Ask and answer questions about invoicing in Italy →