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3 min readBlockingBank of England banking taxonomy 4.1.1Updated 11 November 2026

Credit and counterparty credit risks and free deliveries: IRB approach to capital requirements (CR IRB 1): a total must equal the sum of its parts (OF08.01.01.01, OF02.00.01.01, Bank of England check boe_b0751)

A blocking check on the credit and counterparty credit risks and free deliveries: IRB approach to capital requirements (CR IRB 1) (OF08.01.01.01) and own funds requirements (CA2) (OF02.00.01.01) templates, in the own funds (PRA001) return.

Line4 Check runs it on the own funds (PRA001) return, proven on test files, check by check: the same outcome on all three test files of that return.

Check your file for this ruleWhat to do if it fails

The rule in plain words

RWEA after adjustments should be equal to the sum of RWEA before adjustments, PMAs, unrecognised exposure adjustments and adjustment due to the Mortgage risk weight floor

In each of 18 rows (listed below) of Credit and counterparty credit risks and free deliveries: IRB approach to capital requirements (CR IRB 1) (OF08.01.01.01): "Risk-weighted exposure amount" (column 0260) must equal the sum of "Risk-weighted exposure amount pre-adjustments" (column 0251), "Adjustment to risk-weighted exposure amount due to post-model adjustments" (column 0252), "Adjustment to risk-weighted exposure amount due to mortgage risk weight floor" (column 0253) and "Unrecognised exposure adjustments" (column 0254).

The headline gives only the template and the kind of check, because the rule is too long to say in a headline. The plain words above say all of it.

What to do if your return fails it

  1. 01Open the tables below and find the cells the rule reads.
  2. 02Add up the parts in your return and compare the result with the total.
  3. 03If they differ, a part is missing, a value sits in the wrong cell, or the total is out of date.
  4. 04The Bank of England allows a small rounding difference, worked out from the decimals each value is reported with.
  5. 05It runs only when your filing indicators mark OF08.01.01 as reported.
  6. 06This is a blocking check. A return that fails it is normally rejected, so fix it before you submit.

The cells it reads

Own funds requirements (CA2) (OF02.00.01.01)

Rows

  • R0271Institutions
  • R0295Corporates - Financial corporates and large corporates
  • R0296Corporates - Other general corporates SME
  • R0297Corporates - Other general corporates non-SME
  • R0310Exposures subject to the AIRB approach
  • R0350Corporates - Specialised lending exposures
  • R0355Corporates - Other general corporates SME
  • R0356Corporates - Other general corporates non-SME
  • R0382Retail - Secured by residential immovable property SME
  • R0383Retail - Secured by residential immovable property non-SME
  • R0384Retail - Secured by commercial immovable property SME
  • R0385Retail - Secured by commercial immovable property non-SME
  • R0390Retail - Qualifying revolving
  • R0400Retail - Other SME
  • R0410Retail - Other non-SME

Column

  • C0010All approaches

Credit and counterparty credit risks and free deliveries: IRB approach to capital requirements (CR IRB 1) (OF08.01.01.01)

Rows

  • R000140%
  • R0010Total exposures
  • R0017Of which: Exposures to revolving loan commitments
  • R0020On-balance sheet items subject to credit risk
  • R0030Off-balance sheet items subject to credit risk
  • R003110%
  • R003220%
  • R003350%
  • R0034100%
  • R0035Own estimate
  • R0040Securities Financing Transactions netting sets
  • R0050Derivatives & Long Settlement Transactions netting sets
  • R0060From Contractual Cross Product netting sets
  • R0070Exposures assigned to obligor grades or pools: Total
  • R0175Purchased receivables
  • R0180Dilution risk: total purchased receivables
  • R0190Corporates: where a credit risk assessment by a nominated ECAI is not available
  • R0200of which: investment grade

Columns

  • C0251Risk-weighted exposure amount pre-adjustments
  • C0252Adjustment to risk-weighted exposure amount due to post-model adjustments
  • C0253Adjustment to risk-weighted exposure amount due to mortgage risk weight floor
  • C0254Unrecognised exposure adjustments
  • C0260Risk-weighted exposure amount

Sheets

  • S0001Total (AIRB approach)
  • S0002Total (FIRB approach and slotting approach)
  • S0006Institutions (FIRB approach)
  • S0009Corporates - Specialised Lending (AIRB approach)
  • S0010Corporates - Specialised Lending (FIRB approach or slotting approach)
  • S0011Corporates - Other general corporates - non-SME (AIRB approach)
  • S0012Corporates - Other general corporates - non-SME (FIRB approach)
  • S0015Retail - Qualifying revolving (AIRB approach)
  • S0016Retail - Other SME (AIRB approach)
  • S0017Retail - Other non-SME (AIRB approach)
  • S0018Retail - Secured by commercial immovable property SME (AIRB approach)
  • S0019Retail - Secured by commercial immovable property non-SME (AIRB approach)
  • S0020Retail - Secured by residential immovable property - SME (AIRB approach)
  • S0021Retail - Secured by residential immovable property non-SME (AIRB approach)
  • S0022Corporates - Financial corporates and large corporates (FIRB approach)
  • S0023Corporates - Other general corporates - SME (AIRB approach)
  • S0024Corporates - Other general corporates - SME (FIRB approach)

Which returns it applies to

Line4 Check runs it on the own funds (PRA001) return on Bank of England banking taxonomy 4.1.1. The Bank of England applies it to own funds (PRA001) returns, as a blocking check.

The Bank’s own words and formula

The first paragraph of the plain words above is the Bank of England’s own, word for word, from its list of validations. The second spells out its formula, with each cell named from its templates.

Show the formulaShow

The Bank of England's formula. Cells are written as {t: table, r: row, c: column}.

{t: OF08.01.01.01, c: 0260} = sum({t: OF08.01.01.01, c: 0251; 0252; 0253; 0254})

Where it applies, in the Bank's words (its scope):

scope({t: OF08.01.01.01, r:0001;0010;0017;0020;0030;0031;0032;0033;0034;0035;0040;0050;0060;0070;0175;0180;0190;0200,z:0001;0002;0006;0009;0010;0011;0012;0015;0016;0017;0018;0019;0020;0021;0022;0023;0024, f: banking, fv: banking_reporting})

Every PRA banking rule on OF08.01.01.01

Checks like this one, run at the point of submission, are the first step to real-time supervision. Line4 builds SupTech software for financial regulators that runs checks like these as each return arrives.