Line4

Solvency II validation rules, checked in your browser

For insurers and reinsurers in the EU and EEA that file Solvency II QRTs. Line4 Check runs EIOPA's own validation rules on your quarterly and annual returns, solo, group and third-country branch, in XBRL-XML: taxonomy 2.8.2 for the 2026 returns, 2.10.0 from the first quarter of 2027 (live now on 2.8.2 and 2.10.0). Your file never leaves your computer.

LiveLive for 9 Solvency II returns on taxonomy 2.10.0 and 2.8.2: 16,631 of EIOPA's 16,649 checks for them (all but 18), every one proven against Arelle, the reference XBRL processor, or from EIOPA’s own taxonomy.

Drop your Solvency II QRTs here

One XBRL-XML instance (.xbrl), or a .zip holding just that file, for one of the 18 Solvency II returns listed below, on EIOPA taxonomy 2.10.0 or 2.8.2. Each file is checked against the rules of the taxonomy release its schemaRef names.

Your file never leaves your computer. It is checked inside this browser tab: nothing is uploaded, and nothing from the file is recorded.

Filing to the PRA? Use the Solvency UK checker: UK returns are built on the Bank of England's own taxonomy and checked against its rules. Solvency UK reporting explains the differences.

What we record

Your file is checked in your browser and never uploaded. This is all Line4 keeps about each check, here and on regulators’ websites that show Line4 Check.

For each check, Line4 records

  • Which return was checked and on which EIOPA taxonomy release, such as quarterly solo on 2.10.0
  • The file format: XBRL-XML
  • The kind of result: passed, warnings only, blocking errors, nothing could be checked, or a return not covered
  • The address of the page the check ran on, without anything after a ? or #
  • The date and time
  • Visits and clicks, counted by Vercel Web Analytics without cookies

Never recorded

  • Your file, or any part of it: it is checked in your browser and never uploaded
  • The file name
  • The entity, its LEI or the reporting date
  • Any value or message from the file, or which or how many checks failed
  • Who you are: no name, email, cookie or IP address is kept with the record

If you ask for the report by email, that report (not your file) and your email address are sent to Line4. See the privacy policy.

New to Solvency II reporting? Read the guides to Solvency II reporting and what changes on 30 January 2027. Need the templates? Every Solvency II QRT is listed in plain English, with the returns it goes in. Got a rule code back, such as BV1014? Every one of the 2,691 Solvency II rules Line4 Check runs is explained in plain words, with what to do if your return fails it. All 17 Solvency II returns are in Line4's library of regulatory returns, in plain English, with who files each one, when and in what format. Want this at the gate for every return your insurers file? See Line4's software for insurance supervisors. Need premium support or bespoke validation, such as your national templates? Contact us.

A check at submission is the first step to real-time supervision.

When a QRT is checked the moment it is filed, problems are fixed while the figures are fresh, and what reaches the supervisor is right when it lands.

That is what real-time supervision of insurers needs: validated data, sent straight from insurers' systems, that supervisors can use as soon as it arrives. Line4 Check shows the first step on your own computer. For supervisors, Line4 builds the rest.

What is real-time supervision? →Validation at the gate, for insurance supervisors →

What Line4 Check checks

EIOPA publishes its validation rules with each taxonomy release, as XBRL formulas and in a workbook. Many are written out once per line of business or per row, and each written-out check counts once here. The list leaves out the checks EIOPA has switched off, and those that can never run on a return because none of its templates has the cells they read. Each figure comes from the compiled rule files themselves.

Solo undertakings

  • Quarterly reporting, solo undertakings (QRS)Taxonomy 2.8.2524of 525 · all but 1Taxonomy 2.10.0518of 519 · all but 1
  • Annual reporting, solo undertakings (ARS)Taxonomy 2.8.22,322of 2,325 · all but 3Taxonomy 2.10.02,665of 2,668 · all but 3

Groups

  • Quarterly reporting, groups (QRG)Taxonomy 2.8.2399of 400 · all but 1Taxonomy 2.10.0421of 422 · all but 1
  • Annual reporting, groups (ARG)Taxonomy 2.8.21,387of 1,388 · all but 1Taxonomy 2.10.01,749of 1,750 · all but 1

Third-country branches

  • Quarterly reporting, third-country branches (QRB)Taxonomy 2.8.2506of 507 · all but 1Taxonomy 2.10.0500of 501 · all but 1
  • Annual reporting, third-country branches (ARB)Taxonomy 2.8.22,054of 2,057 · all but 3Taxonomy 2.10.02,031of 2,032 · all but 1

With the ECB’s euro area add-ons

  • Quarterly reporting with the ECB add-ons, solo (QES)Taxonomy 2.8.2Not yetTaxonomy 2.10.0Not yet
  • Annual reporting with the ECB add-ons, solo (AES)Taxonomy 2.8.2Not yetTaxonomy 2.10.0Not yet
  • Quarterly reporting with the ECB add-ons, third-country branches (QEB)Taxonomy 2.8.2Not yetTaxonomy 2.10.0Not yet
  • Annual reporting with the ECB add-ons, third-country branches (AEB)Taxonomy 2.8.2Not yetTaxonomy 2.10.0Not yet

Financial stability, for the largest undertakings and groups

  • Quarterly financial stability reporting, solo (QFS)Taxonomy 2.8.2195of 195 · all of themTaxonomy 2.10.0216of 216 · all of them
  • Quarterly financial stability reporting, groups (QFG)Taxonomy 2.8.2334of 334 · all of themTaxonomy 2.10.0361of 361 · all of them
  • Quarterly financial stability reporting, third-country branches (QFB)Taxonomy 2.8.2214of 214 · all of themTaxonomy 2.10.0235of 235 · all of them
All 9 live returns, on taxonomy 2.10.0 and 2.8.216,631of 16,649 · 99%

Public disclosure (APS, APG) and special purpose vehicles (SPV): by Line4's count of the 2.10.0 taxonomy, EIOPA attaches no validation rules to these entry points, so there is nothing to run there.

Every report carries the same line, for example: “This free check runs 518 of EIOPA's 519 checks for quarterly solo returns on taxonomy 2.10.0 (all but 1), every one proven against Arelle, the reference XBRL processor, on test files, and 33 of EIOPA's filing rules for XBRL-XML, some in part. It is not a substitute for your supervisor's own validation.”

What it checks, in plain words

EIOPA's rules test six kinds of thing. Every failed check is shown with EIOPA's rule code, the rule in EIOPA's own words, the value found and the value expected.

01Totals add upA total in a template equals the sum of its parts, such as the balance sheet (S.02.01) against the lines that make it up.
02Templates agree with each otherA figure reported in two templates is the same in both, such as the solvency capital requirement in S.23.01 and S.25.01 for undertakings on the standard formula.
03Figures have the right signAmounts that cannot be negative are not, such as premiums paid to date on open derivatives (S.08.01).
04Required cells are reportedWhen a template is filed, the cells EIOPA requires in it are there; when it is not, its checks do not run.
05Codes are written rightCoded values follow EIOPA’s patterns, such as the complementary identification code (CIC) of each asset.
06The file is written rightHow the instance itself is written, from its schemaRef and filing indicators to units and decimals, under EIOPA’s XBRL filing rules.

An example: the solvency ratio. EIOPA's rule says the ratio an insurer reports must equal its eligible own funds divided by its solvency capital requirement.

The solvency ratio, in template S.23.01 (own funds)
Capital it can count
Total eligible own funds to meet the solvency capital requirement, row R0540. Say 180.
Capital it needs
The solvency capital requirement (SCR), row R0580. Say 120.
The ratio
Ratio of eligible own funds to SCR, row R0620. 180 against 120 is 150%.
Checked by
EIOPA rule BV87 (taxonomy 2.10.0).
What a failed check tells you

Your solvency ratio (row R0620) does not match your eligible own funds divided by your SCR (rows R0540 and R0580). Check the ratio, or the two amounts.

Each failed check comes with the value found, the value expected and the difference.

EIOPA's rule, as it is writtenShow(t: S.23.01.01.01, r: R0620, z: Z0001) reported as {$v1} * (t: S.23.01.01.01, r: R0580, z: Z0001) reported as {$v2} = (t: S.23.01.01.01, r: R0540, z: Z0001) reported as {$v3}

The numbers are illustrative. The rule is EIOPA's, from taxonomy 2.10.0.

Which taxonomy: 2.8.2 or 2.10.0?

Two Solvency II taxonomy releases are in use now, and Line4 Check reads which one your file was built for from its schemaRef, then runs only that release's rules.

Taxonomy 2.8.2For the 2026 returns, up to and including Q4 and annual 2026 (the optional 2.8.2 Hotfix too). Its schemaRef date is 2024-10-15.
Taxonomy 2.10.0For returns from the first quarter of 2027. Its schemaRef date is 2026-06-30.

Returns for Q4 2026 and the 2026 year end are filed in 2027 but still use 2.8.2 (EIOPA Q&A 3504); the new templates apply from the first quarter of 2027 (EIOPA). What goes and what is new: Solvency II taxonomy 2027: what changes on 30 January.

How it works

  1. 01Your browser downloads the engine and the rulesThe Line4 engine with its XBRL-XML reader is compiled to WebAssembly (498 KB). Only the rules of the return you check are downloaded: EIOPA's quarterly solo rules for 2.10.0 are 117 KB. They are kept by your browser for next time.
  2. 02Your file is opened on your computerThe XBRL-XML instance is read in one pass inside the browser tab, in a background worker so the page stays responsive. Its schemaRef says which return and taxonomy release it is. Nothing is uploaded.
  3. 03Every check runs in momentsEach failed check is listed by template, with the value found, the value expected, EIOPA's rule code and the rule in EIOPA's own words. Download it all as a CSV.

What it does not check

  • 18 of EIOPA's 16,649 checks for these returns do not run yet. Most are checks held back because Arelle, the reference processor, never evaluates them on any test file (it misreads one kind of filter on them), so they cannot be proven yet.
  • National templates and rules that some supervisors add on top of EIOPA’s taxonomy.
  • EIOPA rules that are listed in EIOPA’s workbook but not written into the XBRL taxonomy.
  • Full XBRL schema validation beyond what the checks need.
  • Pension funds (EIOPA’s separate pension funds taxonomy). Solvency UK returns for the PRA have their own checker, under the Bank of England’s rules.

Line4 Check is a prototype of the Line4 validation engine, not certified software. Use it to find problems early, and rely on your supervisor's own validation for the result that counts.

Questions

What is a Solvency II validator?

A Solvency II validator checks an insurer's quantitative reporting templates (QRTs) against the validation rules EIOPA publishes with its taxonomy, such as a total that must equal the sum of its parts, before the file goes to the supervisor. Line4 Check does this in your web browser, on the XBRL-XML file itself, and is free to use.

Is there a free EIOPA validator?

EIOPA used to offer one. Its Tool for Undertakings (T4U) helped insurers create and validate Solvency II XBRL, but EIOPA decommissioned it from the second half of 2017 for budget reasons, and it was never updated for taxonomy 2.2.0 or later (EIOPA, Tool for Undertakings page). Line4 Check runs EIOPA's current rules, for taxonomy 2.8.2 and 2.10.0, free and in your browser.

Is my file uploaded?

No. Your file never leaves your computer. Your browser downloads the Line4 engine (WebAssembly) and EIOPA's rules from line4.ai, then opens and checks the file on your own computer. Nothing is uploaded, and nothing from the file is recorded. If you ask for the report by email, only the report you see is sent to Line4, not the file.

What does Line4 record?

For each check: the return checked and its EIOPA taxonomy release, the file format, the kind of result (passed, warnings only, blocking errors, nothing could be checked, or a return not covered), the address of the page it ran on without anything after ? or #, and the time. Never the file or any part of it, its name, the undertaking or its LEI, the reporting date, any value or message, or which or how many checks failed, and no name, email, cookie or IP address with the record.

Which Solvency II returns can I check?

Quarterly reporting, solo undertakings (QRS) on taxonomy 2.10.0; Quarterly reporting, groups (QRG) on taxonomy 2.10.0; Quarterly reporting, third-country branches (QRB) on taxonomy 2.10.0; Annual reporting, solo undertakings (ARS) on taxonomy 2.10.0; Annual reporting, groups (ARG) on taxonomy 2.10.0; Annual reporting, third-country branches (ARB) on taxonomy 2.10.0; Quarterly financial stability reporting, solo (QFS) on taxonomy 2.10.0; Quarterly financial stability reporting, groups (QFG) on taxonomy 2.10.0; Quarterly financial stability reporting, third-country branches (QFB) on taxonomy 2.10.0; Quarterly reporting, solo undertakings (QRS) on taxonomy 2.8.2; Quarterly reporting, groups (QRG) on taxonomy 2.8.2; Quarterly reporting, third-country branches (QRB) on taxonomy 2.8.2; Annual reporting, solo undertakings (ARS) on taxonomy 2.8.2; Annual reporting, groups (ARG) on taxonomy 2.8.2; Annual reporting, third-country branches (ARB) on taxonomy 2.8.2; Quarterly financial stability reporting, solo (QFS) on taxonomy 2.8.2; Quarterly financial stability reporting, groups (QFG) on taxonomy 2.8.2; Quarterly financial stability reporting, third-country branches (QFB) on taxonomy 2.8.2. The list above gives the number of EIOPA's checks each one runs. Each is one XBRL-XML instance (.xbrl), or a .zip holding just that file. Other returns go live one by one, and the list shows each as it does.

Which taxonomy version does it use?

The one your file was built for. A Solvency II instance names its entry point in its schemaRef, with the taxonomy’s date in the address: 2024-10-15 for 2.8.2 (and its optional Hotfix), 2026-06-30 for 2.10.0. Line4 Check runs only the rules of that release. Taxonomy 2.8.2 applies up to and including the Q4 and annual 2026 returns, which are filed in 2027; 2.10.0 applies from the Q1 2027 reference date (EIOPA, and its Q&A 3504). EIOPA DPM and XBRL.

What changes on 30 January 2027?

The Solvency II review applies from that day, and with it new reporting templates. EIOPA’s final report on reporting (30 March 2026) puts the cut at about 22% of the data points solo undertakings report, with 26% fewer quarterly templates and 30% fewer annual ones (36% and 44% for small and non-complex undertakings). The new templates come with taxonomy 2.10.0, from the first quarter of 2027. Our guide sets out what goes, what is new and what stays on 2.8.2. Read the guide.

Can I check a Solvency II return in xBRL-CSV?

No, and you do not need to: insurers file Solvency II QRTs in XBRL-XML. EIOPA’s XBRL Filing Rules ask for one instance document with the .xbrl extension, and its 2.10.0 taxonomy package ships no xBRL-CSV metadata. xBRL-CSV is the format banks use for EBA returns. EIOPA XBRL Filing Rules.

Is this the same as my supervisor's validation?

No. It is a free check to catch problems before you submit. Your national supervisor's own validation decides whether a return is accepted, and it can run checks Line4 Check does not, including any national templates and rules of its own.

What do errors and warnings mean?

EIOPA gives every validation rule a severity. Errors are failed blocking checks, which stop a return being accepted. Warnings are failed non-blocking checks, which your supervisor may still ask you to explain.

Does it check EIOPA's filing rules?

Yes, 33 of them, some in part (EIOPA XBRL Filing Rules, rules S.1.1.(a), S.1.5.(a), 2.1, 1.6.(a), 1.6.1, 1.6.2, 1.7.(b), 1.7.1, S.1.9, S.2.8.(c), 2.9, 2.10, 2.13, 3.1, 3.2.(a), S.2.16, S.2.19, 2.18.(a), S.2.18.(c), S.2.18.(d), S.2.18.(e), S.2.21, S.2.22, 1.4, S.2.7.(b), 2.7, 2.21, 2.22, S.2.15, 3.4, 3.5, S.2.23 and IV.4): how the instance itself is written, such as its schemaRef, filing indicators, contexts, units and decimals.

How do you know the results are right?

Every check Line4 Check runs is compared with Arelle, the open-source reference XBRL processor, on EIOPA’s own sample returns and on test files built so that each check actually runs: the same result and the same counts, check by check, or the check does not ship. 13 checks can never fire as EIOPA wrote them: for example, one would need an amount and a currency code to share a unit, which XBRL never allows. Those are proven from the taxonomy itself, run as written, and counted apart. A check Arelle never evaluates on any test file is held back and listed, not run on trust (18 today, because Arelle misreads one kind of filter on them). Every report says how many of EIOPA’s checks ran. It is a free check, not certified software.

Do you cover UK insurers (Solvency UK)?

Yes, on its own page. UK insurers report to the PRA under Solvency UK, on the Bank of England’s own insurance taxonomy, not EIOPA’s, so their returns are checked against the Bank’s rules: Line4 Check for Solvency UK runs all 2,292 of the Bank’s XBRL validation rules for its 5 quarterly and annual returns on taxonomy 2.2.0, and 49 of its filing rules. The Solvency UK checker · Bank of England.

What about pension funds (IORPs)?

Not yet. Occupational pension funds report on EIOPA’s separate pension funds taxonomy (now 2.9.0), not the Solvency II one. Tell us if you need it.

Is it free?

Yes. There is no account, no upload and no limit on how many returns you check. After a result you can leave your email address to get the report by email, if you want it. For premium support or bespoke validation (your national templates, other returns or formats), contact us at team@line4.ai.

Sources