Class B

Class B is the middle classification tier under the United Kingdom's Misuse of Drugs Act 1971, sitting between the most restrictive Class A and the least restrictive Class C. The Act divides controlled substances across the three classes according to their assessed harm potential; class membership determines the criminal penalties that attach to possession, supply, and production without a licence.

The designation is specific to UK law and carries no implication about how any other country treats the same compound. Tier numbers used in other countries' frameworks do not map onto the UK's three-class structure.

What it means in practice

A substance assigned to Class B becomes a controlled drug: possession without authority, and supply or production without a Home Office licence, are criminal offences. Penalties exceed those for Class C and fall below those for Class A.

Substances enter the classification through the Act itself or through statutory instruments that amend it, typically following a formal assessment by the Advisory Council on the Misuse of Drugs (ACMD). The ACMD is a statutory expert body; its recommendations advise the Home Secretary but do not bind them — ministers make the final decision.

Class B covers several compound families, including amphetamines, cannabis, barbiturates, and certain stimulants and opioid analgesics. A separate instrument, the Misuse of Drugs Regulations 2001, overlays the class structure with a schedule system (Schedules 1–5) governing licensed activities — prescribing, dispensing, possession for medical use. A compound may sit in Class B under the Act while remaining available by prescription under the Regulations.

How jurisdictions vary

"Class B" is a UK domestic term; other legal frameworks use independent systems whose tier numbers do not correspond to it.

The United States schedules substances under Schedules I–V of the Controlled Substances Act, built on different criteria and a different tier structure. A compound in UK Class B may appear in any US Schedule — or none — depending entirely on US regulatory history.

Australia's Poisons Standard uses separate schedule numbering applied differently across states and territories. New Zealand's Misuse of Drugs Act 1975 uses A, B, and C as labels but lists different compounds at each tier with different penalty structures.

Within the European Union, member states maintain independent classification regimes. A substance's UK Class B status says nothing about how France, Germany, the Netherlands, or any other jurisdiction regulates it.

What is contested

The reclassification of cannabis is the most publicly documented case of the government departing from ACMD advice. The ACMD reviewed cannabis in 2008 and recommended it remain in Class C, where it had been placed in 2004. The Home Secretary rejected that recommendation and returned cannabis to Class B in 2009, citing concern about high-potency preparations. Both the council's advice and the government's decision are on the public record.

The episode is regularly cited in policy literature as an illustration that class assignment is a legislative and political act, not a direct output of harm-evidence findings. This entry reports the divergence; it takes no position on whether the classification is proportionate.

Scope and currency

This entry describes the Class B classification under the Misuse of Drugs Act 1971 as it stood in August 2026. It is a general reference definition and is not legal advice. The law in any jurisdiction — including within the United Kingdom — may differ from what is described here, and nothing in this entry should be read as guidance on legal rights, obligations, or exposure.

Per-substance legal status, with its own jurisdiction, date, and cited source, is the record to rely on. See the Legal Status section on each substance page.