From 29 November 2026, the way UK vehicle bodybuilders submit Certificate of Conformity data is changing permanently. This guide explains what the eCoC mandate means, who it affects, what the new process looks like, and how to prepare your operation before the deadline.
What is an eCoC?
An eCoC, or Electronic Certificate of Conformity, is the structured digital version of the paper Certificate of Conformity (CoC) that has long been part of the UK vehicle type approval process.
A Certificate of Conformity is the legal document that confirms a completed vehicle conforms to its approved type. It carries the vehicle identification number (VIN), technical parameters, mass figures, and type approval reference — and it is required before a vehicle can be registered and put into service.
Until now, CoCs for converted and body-built vehicles have typically been produced manually: data transcribed from OEM PDFs into Excel templates, mass figures taken from weighbridge reports, and completed documents issued as Word files or PDFs. That process is familiar. It is also the process the Vehicle Certification Agency is replacing.
What is changing, and when?
For vehicles manufactured from 29 November 2026, manufacturers — including Stage 2 bodybuilders and converters operating under multi-stage type approval — must make Certificate of Conformity data available to the VCA as structured electronic data through the new eCoC submission framework. The requirement covers categories M, N and O approved under the GB or UKNI schemes, including medium series and UKNI EU small series approvals. Vehicles approved under the national small series (NSSTA) schemes are exempt and may continue to use paper CoCs.
The VCA service is being delivered in phases:
- A structured eCoC portal for manual submission (live since 17 June 2026)
- An API for automated, system-to-system submission (live since 17 June 2026)
- A public, VIN-searchable database to follow in a later phase
Submission is per vehicle, not periodic. Every vehicle you complete and certify will require a structured data submission tied to that vehicle’s VIN.
This is not a minor administrative update. It is a fundamental change to how CoC data is created, validated, and submitted.
Key dates
Does this apply to Stage 2 bodybuilders?
Yes. This is one of the most commonly misunderstood points about the eCoC mandate.
Stage 2 bodybuilders and converters — the companies that receive base vehicles and complete them as refrigerated vans, tippers, curtainsiders, tail-lift vehicles, HIAB-fitted trucks, and specialist conversions — carry their own type approval obligations. If you hold a Stage 2 type approval, you have your own eCoC submission obligation.
The practical reality is that most Stage 2 converters in the UK are not yet thinking about this at all. Many are operating under the assumption that eCoC is an OEM problem. It is not.
What does a Stage 2 CoC actually contain?
Understanding the eCoC requirement starts with understanding what data a Stage 2 CoC is supposed to carry. The key data fields include:
- Vehicle identification number (VIN)
- Stage 1 base vehicle approval reference
- Stage 2 type approval reference
- Technical parameters inherited from Stage 1 (engine, transmission, base vehicle mass)
- Completed vehicle mass figures — kerb weight and gross vehicle weight as built
- Axle load data
- Body type and configuration
- Any equipment additions or modifications that affect the technical baseline
That data currently lives in different places across most converters’ operations. The Stage 1 CoC arrives as a PDF from the OEM. Mass figures come from weighbridge records, often as a separate report. Body and equipment details are in build specifications or job cards. Someone manually pulls it together into a template and produces a document.
The eCoC requirement means that data must exist as structured, validated, submittable data — not as a collection of PDFs, spreadsheets, and Word documents assembled per vehicle.
Why the current process will not scale
Errors that currently pass unnoticed in a PDF will generate rejection responses in a structured submission environment. That is the core shift.
The copy-paste-from-PDF approach has worked because the output was a document. No one validated the data programmatically. There was no API checking that your mass figures were internally consistent, or that your VIN matched a known Stage 1 baseline, or that your type approval reference was current. The VCA’s eCoC portal and API change that — submission will involve structured data fields, and validation will occur at the point of submission.
There is a second problem: template diversity. OEMs do not produce Stage 1 CoC documents in a standard format. Different manufacturers use different layouts, different field labels, and different conventions for presenting technical data. A converter working with multiple base vehicle types is currently managing that diversity manually. In a structured data world, that diversity has to be resolved into a consistent data model before submission.
What converters need to put in place
Preparing for eCoC compliance involves four distinct areas of readiness.
- Stage 1 data ingestion. You need a reliable way to extract technical parameter data from Stage 1 CoC documents — regardless of which OEM produced them — and lock that data as the baseline for each vehicle entering your production process. The VIN is the anchor. Everything downstream needs to be tied to it.
- Mass capture and validation. Completed vehicle mass is the data point most likely to cause submission failures. It needs to be captured accurately at the point of completion, validated against the approved type’s gross vehicle weight limits, and held in a format that maps to the eCoC submission schema. Averaged or estimated figures will not be adequate.
- Structured data output aligned to the VCA schema. The VCA eCoC framework is built on structured XML. Your data needs to exist in a format that maps cleanly to that schema before submission. That means having a data model, not just a document template. Getting this right does not require a large-scale IT project — purpose-built tooling handles the data transformation at a cost that will likely be considerably less than you expect, and almost certainly less than the overhead of managing it manually at volume.
- Submission tracking and audit trail. Per-vehicle submission creates a per-vehicle audit obligation. You need to know, for any vehicle you have built and certified, what was submitted, when, and what the VCA’s response was. That is a records management requirement as much as a technical one.
The opportunity inside the obligation
It is worth being direct about something. Converters who approach eCoC purely as a compliance burden to be minimised will find themselves building a parallel process that sits on top of their existing workflows, adding administration without adding value.
Converters who treat eCoC as the moment to properly structure their build data — per VIN, per stage, with validated mass capture — will find that the same data that satisfies the VCA’s submission requirement also creates something genuinely useful: a complete, auditable digital record per vehicle.
That record has value beyond the VCA. Fleet customers increasingly ask for documented evidence of what was done to their vehicles. Insurance and warranty conversations go better when you have a data trail. Recall or quality incidents are far easier to manage when you can pull the complete build record for any affected VIN within seconds.
The eCoC mandate is an obligation. The structured data it requires is an asset — if you build it properly.
Frequently asked questions
When does the eCoC mandate come into force?+
Do I need eCoC if I only produce a small number of vehicles per year?+
Is my current CoC document good enough?+
What format does the VCA require for eCoC submission?+
Can I use a spreadsheet or Excel template to manage eCoC data?+
What happens if my submission contains errors?+
Where does Stage 1 CoC data come from for my submissions?+
How is Xspect helping converters prepare for eCoC?+
What to do now
The 29 November 2026 deadline is closer than it looks, and the submission portal is already live, so there is nothing stopping you preparing and testing today. If your current CoC process involves PDF transcription, Excel templates, and manually assembled documents, the gap between where you are and where you need to be is meaningful. It is not insurmountable, but it does need attention now.
The practical steps are:
- Map your current CoC process. Identify where data is held, how it is assembled, and who is responsible for it.
- Identify your Stage 1 data sources. Which OEMs do you work with, and what format do their CoC documents come in?
- Assess your mass capture process. Is your completed vehicle weight data accurate, vehicle-level, and held in a structured format?
- Identify your submission route. Will you submit via the VCA portal manually, or do you need an automated solution?
Not sure where your current process stands against these requirements? The Xspect eCoC readiness check takes two minutes and gives you a clear picture of where the gaps are.
