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In forceSolvency UK: internal model firmsLast checked 11 November 2026

Internal model outputs (IMO)

A regulatory return listed by the Bank of England (PRA), insurers, United Kingdom.

Selected results of the firm's approved internal model: points on the probability distributions of losses by risk and line of business, and correlations between risks. The PRA uses them to monitor how internal models perform over time and to compare firms. Source

The facts

Who files
Firms using an approved full or partial internal model to calculate their SCR; life firms use templates IM.00 to IM.02, general insurers IM.00 and IM.03. The Society of Lloyd's reports for each syndicate and for the Lloyd's internal model (SS25/15 paragraphs 2.4 to 2.7). Source
How often
Annual, at the same time as the annual quantitative templates (SS25/15 paragraph 2.1). Source
Deadline
With the annual quantitative templates, under the deadlines in Reporting 2.5B (SS25/15 paragraph 2.1): 70 business days after the year end for a solo firm. Source
Format
XBRL-XML. XBRL for entry point IMO, submitted through BEEDS (SS25/15 paragraph 2.1). Source
How it is filed
Filing routes recorded for the PRA: BEEDS (Bank of England Electronic Data Submission portal); Email to the Bank's insurance data mailbox. See how firms file with the PRA.
Status
In force
Legal basis
Group
Solvency UK: internal model firms

Templates (29)

The tables and forms inside the return. Plain name first, the PRA's code in brackets.

  • Content of submission (IM.00.01.01)
  • Basic information (IM.00.02.01)
  • Basic information - ring-fenced funds / matching adjustment portfolios / with-profits funds (IM.00.03.01)
  • Internal model outputs (life) (IM.01.01.01)
  • Internal model counterparty risk (IM.02.01.01)
  • Reserve Risk Outputs - Own Lines, 1 Year Risk (IM.03.02.01)
  • Reserve Risk Outputs - Solvency II Lines, 1 Year Risk (IM.03.02.02)
  • Premium Risk Outputs - Own Lines, 1 Year Risk (IM.03.03.01)
  • Premium Risk Outputs - Solvency II Lines, 1 Year Risk (IM.03.03.02)
  • Premium Risk Outputs - Historical Premiums and Loss Ratios (IM.03.04.01)
  • Losses From Catastrophe Events - 1 Year Risk (IM.03.05.01)
  • Insurance Risk Outputs - Output Correlations Between Firm's Own Lines of Business - 1 Year Risk (IM.03.06.01)
  • Market Risk Outputs (IM.03.07.01)
  • Total Risk and Risk Module Output Distributions - 1 Year Risk (IM.03.08.01)
  • Risk Module Level Output Correlations - 1 Year Risk - Output linear correlations between risk modules (IM.03.09.01)
  • Descriptions of Undertakings own lines of business (LoBs) (IM.03.10.01)
Show all 29 templates
  • Comments Sheet (IM.03.11.01)
  • Content of submission (IMR.00.01.01)
  • Internal model counterparty risk (RFF) (IMR.02.01.01)
  • Total Risk and Risk Module Output Distributions - 1 Year Risk (RFF) (IMR.03.08.01)
  • Reserve Risk Outputs - Own Lines, Ultimate Risk (MO.03.02.01)
  • Reserve Risk Outputs (MO.03.02.02)
  • Premium Risk Outputs - Own Lines, Ultimate Risk (MO.03.03.01)
  • Premium Risk Outputs - Solvency II Lines, Ultimate Risk (MO.03.03.02)
  • Losses From Catastrophe Events (MO.03.05.01)
  • Insurance Risk Outputs - Output Correlations Between Firm's Own Lines of Business - Ultimate Risk (MO.03.06.01)
  • Total Risk and Risk Module Output - Distributions - Ultimate (MO.03.08.01)
  • Risk Module Level Output Correlations - Ultimate Risk - Output linear correlations between risk modules (MO.03.09.01)
  • Total Risk and Risk Module Output - Distributions - Ultimate (RFF) (MOR.03.08.01)

Templates of the v2.2.0 entry point, which applies to reporting reference dates on or after 31 December 2026 (frameworks DIS, IR, IMO and MAL take effect on 1 January 2027). Filings for earlier dates use taxonomy v2.0.2 or v2.1.0. Names are the Bank's template labels in the taxonomy. Source

Validation rules

405 rules, as counted from the PRA's published material. Software can run them exactly as published. Source

How they are written: XBRL Formula 1.0 assertions in the taxonomy package (val folder of each framework), plus an Excel list of every rule with its expression, severity and entry points.

The rules, on bankofengland.co.uk

How they were counted

Distinct rule codes in sheet 'imo' of 'Bank of England Insurance Taxonomy Validations v2.2.0 - IMO.xlsx' (validations zip) whose 'Severity and modules' column names IMO, with 'Include in XBRL' = yes and 'Deactivated' = no (405), less 0 rule codes set to 'Deactivate' on sheet 'Version 2.2.0' of the validation deny list. The sheet lists 407 rule codes for IMO in all; 2 have 'Include in XBRL' = no.

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

Public data

No published data from this return was found. No published data from this return was found on the Bank of England statistics pages checked (insurance aggregate data, annual and quarterly). Source

Official documents (17)

The PRA'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 PRA's reuse terms. This describes what regulators publish. It is not legal or regulatory advice: always rely on the regulator's own text.

Last checked 11 November 2026.