The GB Classification, Labelling and Packaging Regulation governs what must appear on every chemical label placed on the Great Britain market. Its requirements are not a matter of best practice: they are legally mandatory for any manufacturer, importer, or downstream user placing hazardous substances or mixtures on the GB market, regardless of volume supplied. The label elements prescribed by GB CLP are specific, and following the 6th and 7th edition updates to the GB Mandatory Classification and Labelling List, a significant number of chemical labels need to be redesigned before compliance deadlines in 2026 and 2027.
The Mandatory Elements Every Chemical Label Must Carry
Every chemical label placed on the GB market under GB CLP must include the product identifier, which for substances means the chemical name and identification number, and for mixtures the trade name and the identity of substances contributing to the classification. The name, address, and telephone number of the supplier must appear. Where the substance or mixture is hazardous, one or more hazard pictograms, the nine red-bordered diamond symbols corresponding to the hazard class, must be present. The signal word, either “Danger” for more severe hazards or “Warning” for less severe ones, must appear but never both on the same label. Hazard statements setting out the nature and degree of hazard, and precautionary statements recommending measures to minimise risk, complete the core set.
Pictogram sizing is legally specified. Each hazard pictogram must cover at least one fifteenth of the minimum surface area of the label dedicated to required information, with a minimum area of 1 cm² in any case. Measuring only the height of the diamond from point to point and treating that as the size is a common error: the 1 cm² requirement refers to the area of the diamond, not its height.
What the 2026 MCL Updates Change on Labels
The 6th edition of the GB MCL List, published February 2025, introduced new or revised mandatory classifications for 46 substances with a compliance deadline of 15 August 2026. The 7th edition, published September 2025, added 32 more, with a deadline of 22 March 2027. Where a substance in a product portfolio has acquired a new GB MCL classification, the label must be updated to reflect the revised hazard class and category, the corresponding pictogram, any change to the signal word, and updated hazard and precautionary statements. For formulated mixtures containing the affected substances, the classification of the mixture itself must be reassessed and the label updated accordingly/
The space implication is practical. New classifications, particularly serious health hazard categories such as Carcinogenicity 1B or Reproductive Toxicity 1B under the January 2026 WTO-notified proposal for 60 additional substances, bring the GHS08 health hazard pictogram and typically longer, more specific hazard and precautionary statements. Containers that were previously within label space limits may no longer be so after the update.
Practical Layout Guidance
Where label space is genuinely insufficient to carry all required elements at compliant font sizes, booklet or extended content label formats provide a compliant structural solution. The outer face carries pictograms, signal word, product identifier, and supplier details. The inner pages carry the full hazard and precautionary statement set, particularly for products requiring more than the standard six precautionary statements. The 15 August 2026 deadline for 6th edition substances is the immediate priority for any business supplying chemicals in Great Britain.