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In forceInsurers: Solvency II quantitative reporting (EU, EIOPA)Last checked 11 November 2026

Annual Solvency II return, individual insurer, with ECB add-ons (SII_AES)

A regulatory return listed by the National Bank of Belgium (NBB), Belgium.

The annual Solvency II quantitative templates of an individual insurer together with the ECB statistical add-ons, in one XBRL report. Source

Official title: Annual SII reporting (with ECB add-on) SOLO

The facts

Who files
Insurance and reinsurance undertakings under Belgian law and Belgian branches of non-EEA insurers (Annex 3, section I, to NBB_2026_01). Undertakings under Articles 275 and 294 of the insurance supervision act are exempt from systematic reporting; Article 276 undertakings have their own list. Source
How often
Annual; reference date 31/12/2025. Source
Deadline
8 April 2026 for the reference date 31/12/2025. Source
Format
XBRL-XML. Filed in XBRL through OneGate, domain INS, using EIOPA's taxonomy (2.8.2, with NACE 2.1 optional from reference date 31/12/2025). The OneGate XBRL protocol for domain INS (v1.17) gives the envelope and schemaRefs. Source
How it is filed
Filing routes recorded for the NBB: OneGate; NBB Supervision. See how firms file with the NBB.
Status
In force
Legal basis
Group
Insurers: Solvency II quantitative reporting (EU, EIOPA)

Templates (0)

The library lists no templates for this return.

EU return: the templates and instructions are defined by EIOPA. See the library's EIOPA entry eiopa/aes (docs/eiopa/aes.md), eiopa/ars (docs/eiopa/ars.md). Belgian firms use EIOPA's templates and taxonomy. NBB_2026_01 lists the same report codes for Belgian undertakings and for branches of non-EEA insurers; EIOPA's taxonomy has separate entry points for branches (eiopa/aeb). Source

Validation rules

The NBB publishes the checks it runs on this return. They could not be counted from the published material. Software can run them exactly as published. Source

How they are written: EIOPA validation rules in the EIOPA reporting framework (see the EIOPA entry); OneGate taxonomy checks.

The rules are EIOPA's. From reference period 30/09/2025 every file is forwarded to EIOPA in real time and a report can be closed in OneGate only when both the OneGate and the EIOPA validation reports show no errors. The NBB asks firms to avoid unnecessary zeros: more than 10% zeros gives a warning (05/02/2020 news). The CPA page publishes validation tests between the Solvency II reporting and the annual accounts (validatietests.pdf).

How they were counted

Not counted here: the EIOPA's validation rules apply (see eiopa/aes, eiopa/ars).

Counts are in the NBB's own unit, so they are not comparable with other regulators' counts.

Public data

Published only added up across firms. The NBB publishes aggregate statistical data on the insurers it supervises under Article 31(2)(c) of the Solvency II Directive (Template A: numbers of undertakings and amounts of assets, liabilities, technical provisions and own funds by year). No firm-by-firm data from this return are published by the NBB. Source

Where it is published (PDF and Excel)

Official documents (9)

The NBB's own files, with the size and SHA-256 fingerprint of each as downloaded on 11 November 2026, so anyone can tell whether a copy is the same version.

Sources

Every page and document this return's facts were read from.

Knowing exactly what is collected, in what format and under which rules is the first step to real-time supervision. Line4 builds SupTech software for financial regulators that runs checks like these as each return arrives.

Line4's text and records here are free to reuse under CC BY 4.0. Please credit: “Source: Line4 regulatory submissions library (CC BY 4.0), https://www.line4.ai”. The regulators' documents, forms, taxonomies, rules and data belong to them: see NBB's reuse terms. This describes what regulators publish. It is not legal or regulatory advice: always rely on the regulator's own text.

Source: National Bank of Belgium (https://www.nbb.be). Documents copied here are unchanged and are available free of charge on the NBB's website. The plain-English summaries are Line4's own; the NBB does not endorse this library.

Last checked 11 November 2026.