Side by side
Self-register STCs vs use a trader, and portal vs spreadsheet
In short
Handling STCs yourself keeps control and can suit a high-volume business with compliance capacity. Using a trader moves paperwork and, depending on the contract, some risk to someone else. The deciding numbers are your volume, your rejection rate and net dollars per certificate.
Every installer who creates STCs faces the same choice at some point: do it all in-house, or hand the certificates to a buyer who handles the registry, the checking and the sale. This page lays out the trade, and then deals with the quieter question that comes with it, how you track claims either way.
Side by side
| Self-register and sell | Assign to a trader | |
|---|---|---|
| Who creates the STCs | You, through the REC Registry | Created on your claim, typically with the trader acting as assignee |
| Who finds a buyer | You | The trader is the buyer |
| Paperwork | All yours | Shared; many traders pre-check claims |
| Rate | Whatever you negotiate on the day | Published or quoted by the trader |
| Cash flow | Depends on your sale and settlement terms | Depends on the trader’s settlement time |
| Audit exposure | Yours | Depends on the contract; evidence still comes from your job |
| Best for | High volume, a dedicated back office | Lower to mid volume, or anyone who wants a faster cycle |
What self-registering takes
Creating STCs yourself means keeping the full evidence set for each system: photos, serials, forms, product and installer details. It means lodging correctly and in time, finding buyers, managing price risk and handling any Clean Energy Regulator audit. If you have the volume and the discipline, you keep the whole margin. If you do not, errors cost you. See how STC audits work and top STC claim rejection reasons.
What using a trader changes
The trader becomes the buyer, so you do not hunt for one. Many also review your evidence before lodgement, which cuts rejections. What you give up is the freedom to time the market and, depending on the deal, a share of the certificate value. What to ask: the net dollars per STC, when the rate is fixed, how long settlement takes and what happens if a certificate is invalidated. Our how to compare STC traders and choosing a certificate trader checklist set out the full list. For rate fixing, see rate lock vs spot.
Portal or spreadsheet
Whichever route you take, you need to track each claim from job to cash.
| Spreadsheet | Portal | |
|---|---|---|
| Cost | Free or already paid for | May be free, subscription or built into a provider |
| Setup | Minutes | Onboarding time |
| Good at | A few claims a month; flexible columns | Status, evidence upload, reminders, audit trail |
| Weak at | Version control, shared access, missing-evidence alerts | Fit with how your business already works |
| Risk | A mistyped serial or date goes unnoticed | Lock-in to one provider’s workflow |
A spreadsheet is fine until it is not. The tipping point is usually when more than one person touches claims, or when you want to chase an evidence gap before lodgement rather than after. Neither is wrong; keep whichever lets you answer “where is this claim and what does it still need” in ten seconds.
A simple way to decide
Count three numbers over the last quarter. First, how many claims you lodged. Second, how many were rejected, queried or corrected, and how long each took to fix. Third, how much working time went into evidence, lodging and chasing payment. Multiply that time by what your own hour is worth. If the cost of the paperwork and the rejections is greater than what a trader’s terms take from the certificate value, handing over the claim probably pays. If it is lower, and you have someone who enjoys the work, keeping it in-house may be better. Revisit the sums when volume changes, when scheme rules change, or when a new person joins the back office. The mid-scale extension from 1 October 2026 may also bring larger claims into some businesses; see /mid-scale-solar-stcs/ for what that involves.
A fair verdict
Self-registering suits businesses with volume, back-office capacity and a tolerance for audit work. A trader suits those who value a faster cycle and a second set of eyes on the claim. We buy certificates, so we are not a neutral party here: compare us with the in-house option on net dollars and time. We publish a daily rate on /pricing/, charge zero fees and settle established partners within 24 hours; the first claim takes 48 to 72 hours. If you want to try it, see /start-trading/ and how it works. For the installer overview, /installers/.
How we wrote this. Energy Merchants is a certificate trader, so we have a horse in this race. Statements about other providers are taken from their own public websites on the date shown above and are attributed. If something here is out of date, tell the desk and we will fix it.
Sources: Clean Energy Regulator: Small-scale renewable energy systems
Questions
Before you decide
Can an installer register and sell STCs themselves?
Is a spreadsheet enough to track STC claims?
Does using a trader remove audit risk?
More comparisons
Keep comparing
Solar hot water vs heat pump: which is better in 2026
Solar hot water and heat pump water heaters compared for 2026: how each works, how STCs apply, running cost factors, climate and what to check before choosing.
VPP-capable vs VPP-enrolled battery: what the STC rules need
Why VPP-capable is not the same as VPP-enrolled for battery STCs, where enrolment is required (NSW BESS2, WA), and what to tell customers about retailer VPP plans.
Accreditation compared: VEU, NSW ACP, SAA and CEC for installers
VEU accreditation versus using an accredited provider, NSW Accredited Certificate Providers versus traders, and what SAA and CEC cover for solar and heat pump installers.
Compare us on the thing that matters: when the money lands.
Sign up, lodge one claim, and judge us on the settlement. No lock-in, nothing to cancel.