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How Is a Commercial Quantity of Drugs Calculated in Victoria?

How Is a Commercial Quantity of Drugs Calculated in Victoria?

Direct answer

A commercial quantity of drugs in Victoria is set for each drug in Schedule 11 of the Drugs, Poisons and Controlled Substances Act 1981. It is usually measured by the whole weight of the substance, not just the pure drug, and quantities can be combined, which is what fixes the charge you face.

This guide explains how a commercial quantity of drugs is calculated in Victoria, the three quantity thresholds, whether the pure drug or the whole substance counts, how amounts are combined, and why the calculation decides the charge.

Written by

Lauren Tye

Principal Lawyer · Criminal Defence Lawyer

Legally reviewed by

Counsel

Independent legal review · September 2026

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Key takeaways

  • Commercial quantities are set for each drug in Schedule 11 of the Act.
  • There are three thresholds: traffickable, commercial, and large commercial.
  • The quantity is usually measured by the whole substance, not just the pure drug.
  • Amounts of the same drug are added together, and different drugs can be combined.
  • Cannabis is measured by weight or by the number of plants.
  • The threshold reached decides the charge and the maximum penalty.

Who this is for

Written for

  • People charged with drug trafficking who want to understand the quantity
  • Anyone unsure how a commercial quantity is calculated
  • People disputing the amount they are charged with
  • Anyone wanting to understand the Schedule 11 thresholds
  • Family members of someone facing a trafficking charge

Not a substitute for

  • Legal advice about a specific charge and quantity
  • Representation at a committal, plea, or trial
  • Advice on the exact threshold for your drug
  • Advice about the penalties, covered separately
  • Advice about Commonwealth drug offences

Plain-English definitions

Schedule 11

The schedule that sets the traffickable, commercial, and large commercial quantities for each drug.

Traffickable quantity

The lowest threshold, which triggers the deemed trafficking rule.

Commercial quantity

A higher threshold that lifts a trafficking charge to section 71AA.

Large commercial quantity

The highest threshold, which lifts the charge to section 71.

Mixed weight

The weight of the whole substance, including anything the drug is mixed with.

Pure weight

The weight of only the drug itself, used for some drugs.

Aggregation

Adding together amounts of the same drug, or combining different drugs, to reach a threshold.

Drug of dependence

A drug listed under the Act, such as heroin, cocaine, methamphetamine, or cannabis.

Legal process timeline

  1. 1

    The seizure

    Drugs are found and seized by police.

  2. 2

    The weighing and analysis

    The substance is weighed and analysed in a laboratory.

  3. 3

    Comparing to Schedule 11

    The amount is compared to the thresholds for that drug.

  4. 4

    Fixing the charge

    The threshold reached determines the trafficking charge laid.

  5. 5

    Combining amounts

    Where relevant, amounts of the same drug, or different drugs, are combined.

  6. 6

    The brief

    The measurement and analysis form part of the prosecution brief.

  7. 7

    Testing the quantity

    The measurement can be examined and, where appropriate, challenged.

About this guide

Legal basis

This guide is based on the quantity thresholds in Schedule 11 of the Drugs, Poisons and Controlled Substances Act 1981 (Vic) and the way those thresholds set the trafficking charge under sections 71AC, 71AA, and 71.

How this guide was prepared

Drafted for people who want to understand how a commercial quantity is calculated, based on the questions asked when the amount charged is central to the case.

Important limits

This article does not cover every situation. It does not specifically deal with:

  • The exact threshold for every individual drug
  • The precise measurement in your case
  • Bail and penalties, which are covered separately
  • Commonwealth drug importation offences
  • How a specific laboratory analysis was conducted

The exact threshold for a drug should always be confirmed against the current Schedule 11.

In-depth analysis

How Drug Quantities Are Set in Victoria

How is a commercial quantity of drugs calculated?

By reference to the amount set for each drug in Schedule 11. The Act lists, for every drug, the amount that counts as a commercial quantity, and the amount seized is compared to it. Understanding how a case proceeds helps you see why this measurement is so important, because it fixes the charge.

The figures differ by drug. A commercial quantity of one drug is a very different amount from another, so the calculation always starts with identifying the drug and finding its threshold in the schedule.

What are the three quantity thresholds?

There are three, each lifting the charge to a more serious level. The lowest is the traffickable quantity, then the commercial quantity, then the large commercial quantity, and the table below shows how they map to the charge.

ThresholdExample (traffickable)Charge it sets
Traffickable quantityCannabis 250g or 10 plants; heroin or cocaine 3gDeemed trafficking (s71AC)
Commercial quantityA much higher amount per drugCommercial trafficking (s71AA)
Large commercial quantityThe highest amount per drugLarge commercial trafficking (s71)

The traffickable figures shown are confirmed examples, while the commercial and large commercial thresholds are substantially higher amounts set separately for each drug. Because they differ so much between drugs, the exact figure should always be checked against the schedule, and our guide on what a commercial quantity means explains how they apply.

Weight, Mixtures and Combined Amounts

Is it the pure drug or the whole substance that counts?

Usually the whole substance. For most drugs, the quantity is measured by the mixed weight, meaning the total weight of the substance including anything the drug is mixed with, not just the pure drug. For some drugs, the pure weight is used instead.

This can make a significant difference. A substance that is heavily mixed can weigh far more than the pure drug it contains, so whether mixed or pure weight applies, and how it was measured, is often worth examining closely, as it can change the charge.

How are different drugs or amounts combined?

By aggregation. Amounts of the same drug found in different places can be added together, and in some cases quantities of different drugs can be combined so that, together, they reach a commercial threshold even where no single drug does. This is one way a charge can be more serious than it first appears.

Cannabis is treated a little differently, because it can be measured by weight or by the number of plants. As our guide on cannabis cultivation charges explains, the plant count can be as important as the weight in reaching a threshold.

Why Does the Calculation Decide the Charge?

Why does the quantity matter so much?

Because it sets the charge and the maximum penalty. The same conduct can be a lower-level trafficking offence or a commercial or large commercial one depending only on the quantity, and each step up carries a far higher maximum. That is why the calculation is so central to a trafficking case.

A small difference around a threshold can therefore change everything. Where the amount is near a threshold, exactly how it is measured can be the difference between two very different charges, which is why the quantity is rarely accepted without scrutiny.

Can the quantity be challenged?

Yes, in several ways. The weighing, the analysis, whether mixed or pure weight applies, and how amounts were combined can all be examined, and a successful challenge can reduce the charge. Where the measurement is wrong or contestable, it can support charges downgraded or dropped.

This is detailed work. Our team at drug offence defence examines the measurement and analysis closely, because on a trafficking charge the quantity is often where the real contest lies.

Scenario-based guidance

If your amount is near a threshold

How it is measured can change the charge, so the calculation should be examined closely.

If the substance was heavily mixed

Whether mixed or pure weight applies matters, so this should be checked with legal advice.

If drugs were found in different places

Amounts can be aggregated, so how they were combined is worth examining.

If different drugs were combined

Combining drugs can reach a threshold, so how that was calculated should be tested.

If you are charged over cannabis

The plant count can matter as much as the weight, so both should be considered.

If you dispute the quantity

It is an element the prosecution must prove, so it can be challenged.

Practical checklist

If the quantity is central to your charge:
  • Get legal advice about how the quantity was calculated.
  • Confirm which drug and which threshold apply.
  • Check whether mixed or pure weight was used.
  • Examine how the substance was weighed and analysed.
  • Consider whether amounts were aggregated correctly.
  • For cannabis, check both the weight and the plant count.
  • Look at whether your amount is near a threshold.
  • Test whether the measurement is contestable.
  • Confirm the exact threshold against the current schedule.
  • Attend every court date.

Common mistakes

  • Assuming only the pure drug is counted.
  • Overlooking that amounts can be aggregated.
  • Not checking whether the amount is near a threshold.
  • Accepting the measurement without scrutiny.
  • Ignoring the plant count in a cannabis matter.
  • Assuming the threshold is the same for every drug.
  • Not confirming the exact figure against the schedule.
  • Failing to test how the substance was analysed.
  • Treating the quantity as beyond challenge.
  • Delaying legal advice on a serious charge.

Questions to ask your lawyer

  • Which drug and threshold apply to my charge?
  • Was mixed or pure weight used to measure it?
  • How was the substance weighed and analysed?
  • Is my amount near a threshold?
  • Were amounts aggregated, and was that correct?
  • For cannabis, how were the plants counted?
  • Can the measurement be challenged?
  • Could a challenge reduce my charge?
  • What is the exact threshold for my drug?
  • What should I do right now?

Sources

Frequently asked questions

It is set for each drug in Schedule 11 of the Drugs, Poisons and Controlled Substances Act 1981. The amount seized is measured, usually by the whole weight of the substance rather than the pure drug, and compared to the commercial threshold for that drug. The threshold reached determines the trafficking charge.

For most drugs, the quantity is measured by the mixed weight, the total weight of the substance including anything the drug is mixed with, not just the pure drug. For some drugs, the pure weight is used. Because a mixed substance can weigh far more, how it is measured can change the charge.

Yes. Amounts of the same drug found in different places can be aggregated, and in some cases quantities of different drugs can be combined so that, together, they reach a commercial threshold even where no single drug does. This can make a charge more serious than it first appears.

Cannabis can be measured by weight or by the number of plants, so the plant count can be as important as the weight in reaching a threshold. The traffickable quantity is 250 grams or 10 plants, and the commercial and large commercial thresholds are set as higher amounts and plant numbers in Schedule 11.

Yes. The weighing, the laboratory analysis, whether mixed or pure weight applies, and how amounts were combined can all be examined, and a successful challenge can reduce the charge. Where the amount is near a threshold, the measurement is often central, so it is rarely accepted without scrutiny.

Authorship

Written by

Lauren Tye

Principal Lawyer, Lauren Tye Legal
Criminal defence lawyer practising in Victorian criminal matters. Lauren advises and appears in matters across Victorian courts, including bail, pleas, contested hearings, diversion, and sentencing.

Legally reviewed by

Senior Counsel

Independent legal review · September 2026
Criminal defence lawyer practising in Victorian criminal matters. Lauren advises and appears in matters across Victorian courts, including bail, pleas, contested hearings, diversion, and sentencing.

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Need Advice on Your Specific Situation?

The information on this page is general and is not legal advice. Speak with a criminal defence lawyer about your matter before making decisions about police, court, bail, plea, or prosecution.