Why did my STC claim fail validation?

Written and checked by the Energy Merchants desk · Reviewed 2 October 2026 · For installers

Validation is the registry’s first line of checks. If a claim fails, the cause is nearly always visible if you know where to look.

The usual reasons

Data mismatches. System size, panel count, inverter model or postcode do not match what the registry expects. Typos in serial numbers are common.

Eligibility. The product is not on the approved list on the install date, or the installer’s accreditation was not current.

Missing documents. A required form, signature or photo is not attached.

Duplicate or overlapping claims. The same address and system already have a claim. This often arises with additions or resubmitted jobs.

Installation type and zone. The classification or postcode zone drives the STC count. A mismatch triggers a query.

How to read the failure

Open the claim in the registry and read the message. If it is unclear, ask your trader’s compliance desk, who read these every day. Compare it against your own job file, including the quote, the serials list and the photos.

What to do next

1. Identify the specific field or document at fault.
2. Check against the photo requirements and assignment form guide.
3. Correct and resubmit, following how to fix a failed claim.
4. If it is an eligibility problem, speak to your trader before spending more time.

Typing errors that cost days

A transposed digit in a serial number, a wrong inverter model code, a postcode that does not exist, a capacity entered as inverter size instead of panel total, or a date in the wrong year will each trigger a check. These are not eligibility problems, but they look like them in the system. Using data captured directly from a product label or a barcode scan, rather than typed, removes most of them. Where typing is unavoidable, a second person should read the numbers back.

What this means for installers

Get the data right at the source: serials captured from the unit, not retyped, and zone and classification set on the job sheet. A trader who pre-checks claims will catch most of these before lodgement. See how it works, the STC trading page and the resources hub.