ISCC EU · UCO traceability
ISCC EU mass balance does not reconcile? Five checks for UCO businesses
A practical ISCC EU mass balance checklist for used cooking oil collectors and traders: reconcile stock, transactions, sustainability credits and certificate dates.
Your used cooking oil stock report shows one figure, the mass balance shows another, and the sustainability declarations appear to support a third. Before changing a spreadsheet formula, establish whether the difference comes from physical quantities, transaction timing or sustainability eligibility.
This guide focuses on ISCC EU UCO collecting and trading operations. It is not a universal rule set for ISCC PLUS, CORSIA, processing or gaseous fuels. Confirm the documents and updates applicable to your scope with your certification body.
1. Fix the boundary and period first
ISCC EU 203 requires clear mass balance periods, material and site boundaries, and traceable inputs, outputs and stock. For operators other than the specified agricultural/forest biomass categories, the maximum period is three months; periods must be continuous. An annual summary alone does not demonstrate period-by-period compliance.
Write the site, material, scope, opening date and closing date at the top of the working sheet. Check that the opening position agrees with the preceding close. Keep a dated copy of the original workbook before investigating differences.
2. Reconcile physical quantities independently
For a simple storage-only example, start with opening stock, add receipts and subtract dispatches. Record supported adjustments separately. Processing operations need additional treatment of yields and conversion factors.
Illustrative example: opening stock of 20 tonnes plus 100 tonnes received, less 90 tonnes dispatched, gives an expected physical close of 30 tonnes before adjustments. If a stocktake shows 27 tonnes, the three-tonne difference needs investigation. It is not automatically a processing loss or a sustainability-credit adjustment.
Trace the difference through tank readings, collection records, weighbridge tickets and dispatch dates. Look for duplicated imports, omitted movements and inconsistent units. Where litres are converted to tonnes, retain the conversion basis used. Do not choose a conversion factor simply because it makes the spreadsheet balance.
3. Reconcile sustainability credits separately
Physical inventory and sustainability credits answer different questions. ISCC EU credit transfer is limited by the equivalent eligible physical stock of the specific material at period end. The scheme's mass balance guidance also links claims to physical material flows and distinguishes materials and product groups.
For a separate simplified example, assume valid opening credit of 10 tonnes, eligible input credit of 60 tonnes and outgoing claims of 50 tonnes, with no other adjustments. The preliminary credit balance is 20 tonnes. If only 15 tonnes of the relevant material remain physically in stock, carrying all 20 tonnes forward would require correction under the applicable rules. Retain the calculation and explanation rather than silently overwriting the opening credit next period.
4. Trace transactions in both directions
Choose a dispatch and follow it backwards through the sustainability declaration, sales record, delivery evidence and input records. Then choose a receipt and trace how it entered the balance. This is a practical reconciliation exercise, not a prescribed audit sample size.
Check whether collection date, invoice date and delivery date have been confused. If a transaction is recorded differently across systems, keep the original evidence and explain the agreed treatment. Make a difference log with the transaction reference, quantity, reason, action owner and resolution.
5. Investigate certificate gaps and suspensions explicitly
Create a timeline of certificate validity, expiry, suspension and reinstatement using the certification body's correspondence and relevant certificate records. Flag affected receipts, dispatches, claims and stock entries for review. Keep commercial movements visible while their sustainability treatment is resolved.
Do not assume a later certificate retrospectively makes earlier transactions eligible, or apply a blanket withdrawal or downgrade to every stock entry without establishing the applicable treatment. Refer the affected transactions and evidence to the certification body and document its determination.
Prepare a precise ISCC enquiry
Get-ISO coordinates ISCC certification enquiries with BM Certification. Describe your activities and the specific reconciliation issue so the appropriate scope and technical review can be established. Start with our ISCC enquiry checklist.
Official references
- ISCC EU 203, version 4.2: Traceability and Chain of Custody, section 4.4.
- ISCC EU 203-02: Mass Balance Guidance, version 1.2.
- ISCC document library for applicable documents and system updates.
The figures and investigation workflow above are simplified illustrations, not client data or a certification determination.
General guidance. Use the applicable standard, scheme documents and agreed engagement criteria. Examples are illustrative and do not establish a certification outcome.