Assurance · audit trail · ISSA (UK) 5000
Sustainability assurance software: make the trail before anyone asks
Sustainability assurance software, for a reporting company, means keeping ESG data audit-ready: every reported figure traceable to its source.
Assurance is voluntary in the UK, but listed companies now have to say whether they obtained it.
Assurance itself is explained on the sustainability assurance guide.
Status
Is sustainability assurance required?
No UK entity is required to obtain sustainability assurance; the FRC issued ISSA (UK) 5000 on 12 November 2025 for voluntary use, effective 15 December 2026 (FRC).
Under PS26/19 a listed company states whether its UK SRS disclosures were assured and, if so, by whom and against which standard; it does not have to explain why it did not obtain assurance (FCA).
ISAE 3410, the old greenhouse gas assurance standard, is being withdrawn (IAASB).
What it means
What should assurance-ready software never claim?
A limited assurance conclusion is never a positive statement that the information is correct; it says nothing has come to the provider’s attention suggesting a material misstatement.
So software should not label assured figures as "verified" or "certified".
GHG statements can also be verified to ISO 14064-3, which ends in a verifier’s opinion at reasonable or limited assurance (ISO); see ISO 14064 software.
Audit-ready ESG data
What makes ESG reporting software audit-ready?
Four things: a trail from each reported figure to its source record, the method and factor version applied, the owner and review history, and an export the provider can sample from.
That is the same data model as good sustainability data management software.
For the disclosure statement itself, see ESG disclosure software.
The demonstration
What should you test before buying?
Ask the vendor to prepare the sample an assurance provider would request.
Software demo · evidence check
Assurance readiness demo coverage
Tick a test only when the vendor has demonstrated it with a representative record and shown the evidence or export.
0 of 5 tests demonstrated (0%). This is a checklist result, not a score for the vendor.
Still to test: Trace three reported figures back to source records; Show the method, factor and version behind each; Show who entered, reviewed and approved each value; Record whether assurance was obtained, by whom and to which standard; Export a sample-ready evidence pack.
Frequently asked
Sustainability assurance software, answered
What is sustainability assurance software?
Either software assurance providers use to plan and document engagements, or, more often for companies, software that keeps ESG data audit-ready: every figure traceable to its source, method and owner.
Is sustainability assurance mandatory in the UK?
No. No UK entity is required to obtain sustainability assurance.
ISSA (UK) 5000 was issued for voluntary use and is mandatory for no one.
What does PS26/19 ask about assurance?
A listed company says whether its UK SRS disclosures were assured and, if so, by whom, which disclosures and against which standard.
Does limited assurance mean the figures are correct?
No. A limited assurance conclusion is a double negative: nothing has come to the provider’s attention suggesting a material misstatement. It is never a positive statement that the information is correct.
Sources
Primary sources
Every figure, date and status on this page traces to the instrument’s owner.
Secondary commentary is never the source for a number.
- FRCISSA (UK) 5000
- FRCAudit, assurance and ethics standards
- FRCSustainability reporting developments FAQ
- FCAPS26/19 (PDF)
- IAASBWithdrawal of ISAE 3410
- ISOISO 14064-3:2019 verification
- UKASValidation and verification accreditation
- DBTUK SRS S1 General Requirements
- EUR-LexDirective 2013/34/EU, consolidated 18 March 2026