Commercial gas broker: What they do & how it works

A commercial gas broker helps businesses compare gas retailers, interpret the pricing structure behind quotes, and negotiate contract terms, then coordinates the paperwork to switch or renew with minimal disruption. In practice, a good broker makes it easier to secure a suitable business gas contract by turning confusing offers into a like for like comparison, with clear trade-offs around price certainty, risk, and flexibility.

This guide explains what a commercial gas broker does in Australia, how business gas contracts typically work, how gas is measured and billed in MJ and GJ, and the common pricing structures you will see in quotes.

What is a commercial gas broker?

A commercial gas broker is an intermediary that helps a business procure natural gas from one or more gas retailers. The broker does not own the pipelines or supply the gas itself, instead they manage the comparison and procurement process, so you can make a decision with clearer information and less admin.

You will also see the terms business gas broker and gas procurement broker used to describe a similar role.

What does a commercial gas broker do day to day?

While services differ by provider and by customer size, a typical commercial gas broker can help with:

Bill review and data capture: collecting recent invoices, usage history, and your site identifier, usually the Meter Installation Registration Number (MIRN).
Usage profiling: checking seasonality and drivers of consumption, for example winter heating, hot water load, process heat, or kitchen demand.
Quote requests: approaching a panel of retailers that service your network area and meter type.
Offer normalisation: translating quotes into a comparable view, for example converting c/MJ to $/GJ and aligning assumptions.
Explaining pricing structures: fixed vs variable, what is included vs pass-through, and where your risk sits.
Negotiation: seeking improved unit rates, supply charges, and better non-price terms.
Contract support: reviewing term length, start dates, credit requirements, and key clauses.
Switch coordination: helping ensure the transfer is executed correctly and that your first bill aligns with the agreed rates.

How business gas contracts work in Australia

Most business gas arrangements fall into one of two broad buckets:

Small business market contracts: often simpler, typically priced as a daily supply charge plus a usage rate (c/MJ). These may include conditional discounts and have standard terms.
Large market or negotiated contracts: tailored pricing and terms, often for higher-usage sites, multi-site portfolios, or industrial loads. These may include more complex risk settings and pass-through components.

In both cases, your contract is with a retailer. The physical gas network, pipelines, and metering are typically managed by separate entities. Changing retailers usually changes billing and contract terms, not the pipes serving your site.

Common contract elements you will see in gas offers

Term length: often 12, 24, or 36 months, sometimes longer for negotiated tenders.
Start date: aligned to your current contract end date or a nominated transfer date.
Usage rate: c/MJ or $/GJ, sometimes tiered by volume bands.
Daily supply charge: a fixed $/day amount, can materially impact smaller users.
Fees and adjustments: billing fees, paper bill charges, late payment fees, and sometimes indexation mechanisms.
Exit terms: early termination fees, make-good clauses, or notice periods.
Credit and security: credit checks, deposits, or guarantees, especially for larger users.
Volume assumptions: minimum take, volume tolerance bands, or re-pricing triggers if usage shifts materially.

MJ vs GJ, how gas is measured and priced

In Australia, natural gas usage is commonly billed in megajoules (MJ) or gigajoules (GJ).

1 GJ = 1,000 MJ
If your quote is 4.0 c/MJ, that is the same as $40/GJ (because 4.0 cents times 1,000 equals 4,000 cents, which is $40).

Retailers may quote in c/MJ (common in some small business offers) or $/GJ (common in commercial tender responses). A broker will often convert units so you can compare offers properly.

Why MJ and GJ matters when comparing quotes

It reduces confusion: Many businesses accidentally compare a c/MJ figure to a $/GJ figure and assume one is cheaper.
It supports like for like analysis: Especially when one offer is bundled or presented differently.
It helps with budgeting: Converting to a consistent unit makes annual cost modelling easier.

Commercial gas pricing structures explained

Gas quotes can look similar on the surface but behave very differently over time. The key is understanding how the unit rate is built, and what can change during the contract.

1) Fixed price gas contract

A fixed contract generally locks in a usage rate for the term, giving stronger budget certainty. This can suit businesses that value predictability and have limited appetite for market movements.

Watch-outs: Fixed does not always mean everything is fixed. Some elements may still be pass-through depending on the contract, for example certain network or regulatory charges.

2) Variable price gas contract

A variable contract means your price can move during the term based on an agreed mechanism, for example retailer rates, published indexes, or periodic re-pricing. This can suit businesses willing to accept price movement in exchange for flexibility or potential downside benefit if markets soften.

Watch-outs: You need to understand when rates can change, how often, and whether the retailer has discretion.

3) Pass-through, bill split, or component based structures

For larger customers, offers may separate the commodity component from other charges. You might see language such as:

All-inclusive: One bundled $/GJ rate that includes agreed components.
Partially inclusive: Some items included, some passed through at cost.
Pass-through: More items are charged as they occur, which can reduce retailer risk premium but increases your exposure to changes.

A good procurement broker will highlight which elements are included and which are variable, so internal stakeholders understand the risk profile.

4) Volume banding and seasonal load considerations

Many businesses use more gas in winter. Some retailers price based on annual volume bands, while others place conditions around usage tolerance. If your operations change, for example you install electric heat pumps, close a kitchen, or add a second shift, your usage could shift and you may trigger re-pricing clauses.

5) Supply charge vs usage rate trade-offs

Smaller businesses can be heavily impacted by the daily supply charge. Two offers can have the same c/MJ rate but different supply charges, leading to different annual costs. Always compare the total estimated annual cost, not just the headline usage rate.

What you need before you go to market for a gas contract

To obtain accurate quotes, you typically need:

MIRN and supply address for each site
Recent gas bills, ideally 12 months for seasonality
Current contract end date and any notice requirements
Preferred term length and risk preference, for example fixed vs variable
Any operational changes expected during the next 12 to 36 months

How a gas procurement process typically runs

Scoping: confirm sites, volumes, and timelines.
Data validation: check bills, meter identifiers, and usage totals.
Market engagement: request quotes from relevant retailers.
Comparison: convert units (MJ, GJ), align assumptions, and compare total annual cost and terms.
Negotiation: improve pricing and reduce unfavourable terms where possible.
Decision and contracting: sign with the chosen retailer.
Transfer and first bill check: confirm your first bill reflects agreed rates and dates.

How commercial gas brokers get paid

Broker remuneration varies. Common models include:

Retailer-paid commission: The retailer pays a commission to the broker, often built into the contracted rate.
Fee for service: The business pays a consulting fee for procurement and analysis.

Whichever model applies, ask for clear disclosure so your business understands incentives and governance requirements.

Questions to ask before choosing a business gas broker

Which retailers are on your panel for my state and network area?
How are you paid, and is any commission built into the rate?
Will you provide a like for like comparison with total annual cost?
Which charges are fixed, and which are pass-through?
Do you help validate the first bill and support issues during the term?
Can you support multi-site portfolios or a combined gas and electricity procurement?

How Zembl helps with commercial gas procurement

Zembl helps Australian businesses compare gas offers from a panel of retailers, understand pricing structures clearly, and switch with less admin. If you want to run a wider procurement process across both fuels, we can also help you review combined gas and electricity offers and align contract dates across sites.

Frequently asked questions

Is it worth using a commercial gas broker?

It can be, especially if you do not have time to approach multiple retailers, if you need help interpreting pricing structures, or if you have multiple sites or a higher spend. The key is transparency on how the broker is paid, and a clear comparison that focuses on total cost and contract terms.

Does switching gas retailers interrupt supply?

In most standard switches, no. The change is typically administrative, the network stays the same, and the retailer responsible for billing changes. Timing can depend on meter data and correct site identifiers.

What is a good commercial gas rate in Australia?

There is no single best rate because pricing varies by location, usage volume, contract term, and market conditions. Focus on comparing like for like offers, and consider both the unit rate ($/GJ or c/MJ) and the daily supply charge, as well as any pass-through components.

What is the difference between MJ and GJ on my gas bill?

MJ and GJ are units of energy. 1 GJ equals 1,000 MJ. If you convert all quotes into the same unit you can compare pricing more accurately.

Next step

If your gas contract is approaching renewal, or you want to understand whether your current rate is competitive, share a recent bill and we can help you compare options and explain the contract structure before you decide.