Is Net Weight Required on a CLP Label?

Short answer: no.

However, that answer on its own is incomplete and often misunderstood.

Wax melts sit at the intersection of several different legal requirements, which are frequently treated as one. In practice, this leads to both under-labelling and over-labelling.

This article explains how the rules actually work under UK / GB law.

The legal frameworks involved

Wax melts sold to consumers typically fall under three separate areas of law:

• CLP Regulation – hazard classification, labelling, and identification
• Weights and Measures legislation – quantity marking for consumer goods
• General product safety and consumer protection law – accuracy, clarity, and enforcement

Each framework has a different purpose. None of them replace the others.

What CLP regulates 

CLP (Classification, Labelling and Packaging) governs hazard communication.

Its purpose is to ensure that hazardous substances and mixtures are:

• clearly identified
• correctly classified
• appropriately labelled
• traceable to a responsible supplier

CLP does not regulate how products are sold by quantity, and it does not set rules for weights and measures.

What CLP requires on a label

Under Article 17 of the retained GB CLP Regulation (EC) No 1272/2008, a CLP label must include, among other things:

“the product identifier”

“the nominal quantity of a substance or mixture in the package made available to the general public, unless this quantity is specified elsewhere on the package”

— Article 17(1)(f), Regulation (EC) No 1272/2008 (GB CLP)

CLP does not define nominal quantity as net weight, and it does not prescribe the units in which quantity must be expressed.

What “nominal quantity” means under CLP

Under CLP, nominal quantity is about identification, not measurement.

Its function is to help identify the hazardous mixture and distinguish it from similar products.

This is reflected in ECHA guidance, which explains that nominal quantity is intended to:

“help to identify the substance or mixture and distinguish it from other products”

— ECHA Guidance on Labelling and Packaging

For wax melts, valid examples of CLP nominal quantity include:

• “6 wax melts”
• “1 snap bar”
• “12 segments”
• “1 clamshell”

These descriptions identify what the product is. They do not describe how much it weighs.

Does CLP require net weight?

No.

There is no requirement in CLP to display grams, kilograms, or net weight.

A CLP label can be fully compliant without any weight shown, provided the product is clearly identifiable and all other CLP elements are present.

The important distinction: net weight may still be required

Although CLP does not require net weight, UK Weights and Measures legislation often does.

This obligation exists separately from CLP and is not overridden by it.

Where the net weight requirement comes from

Net weight marking is required under Weights and Measures / Packaged Goods legislation, not CLP.

Under The Weights and Measures (Packaged Goods) Regulations 2006:

“A prepacked product shall be marked with an indication of its nominal quantity.”

— Regulation 5, Packaged Goods Regulations 2006

Although the same term is used, “nominal quantity” does not mean the same thing here as it does under CLP.

What “nominal quantity” means under Weights and Measures

Under Weights and Measures law, nominal quantity is a measurement concept, not an identification one.

For solid prepacked goods, nominal quantity means:

• the net weight of the product, excluding packaging

This quantity is used to ensure consumers receive what they pay for and to allow enforcement using average weight and tolerances.

In simple terms:

• CLP uses nominal quantity to identify the hazardous product
• Weights and Measures uses nominal quantity to measure how much product is supplied

The shared wording does not mean the requirements are interchangeable.

Does selling by number remove the weight requirement?

No.

The legislation does not restrict weight marking to products “sold by weight”. It applies to prepacked goods, regardless of whether the product is marketed as:

• “6 wax melts”
• “1 snap bar”
• “a clamshell”

A numerical description may satisfy CLP nominal quantity, but it does not automatically remove the requirement to show net weight under Weights and Measures law.

Where net weight must appear

Weights and Measures legislation requires net weight to be:

• clear
• legible
• displayed on the product or its packaging

It does not require net weight to appear on the CLP label itself.

If net weight is shown, is nominal quantity still needed on the CLP?

In most cases, yes.

Net weight fulfils consumer quantity requirements. Nominal quantity supports CLP product identification.

Weight alone does not always clearly identify the product. For example, “Net wt 60g” could describe six wax melts, a single snap bar, or mixed shapes.

Weight variation and handmade products

Declared net weight is treated as an average, not a guaranteed exact weight for every individual pack.

Handmade products are expected to vary. You are not required to make every melt identical, print different weights per pack, or relabel individual products.

Are there legal tolerances?

Yes.

The Packaged Goods Regulations operate on an average quantity system, with defined tolerances for underweight packs only.

For a declared net weight of 60g (50–100g band):

• Maximum permitted negative error (T1): 4.5g
• No pack may exceed the T2 limit (double T1)
• The average of the batch must meet or exceed the declared weight

— Schedule 3, Packaged Goods Regulations 2006

There is no maximum permitted weight and no offence for being overweight.

Why some businesses are told to remove weight

Some businesses report being advised by Trading Standards to remove net weight from their product. This advice is usually context-specific and does not alter the legislation itself.

Common reasons include inaccurate weight declarations, conflicting quantity information, or enforcement decisions based on how a product is presented.

Trading Standards enforce the law on a case-by-case basis. Advice given to one business does not create a universal rule.

Key points 

• CLP does not require net weight
• Net weight is often still required under Weights and Measures law
• Nominal quantity and net weight are not the same thing
• Showing one does not automatically replace the other
• Including both is often the clearest and lowest-risk approach

Legislative references

• Regulation (EC) No 1272/2008 (GB CLP), Article 17
• ECHA Guidance on Labelling and Packaging
• Weights and Measures Act 1985
• Weights and Measures (Packaged Goods) Regulations 2006, Regulation 5 and Schedule 3

---

FAQ – Nominal Quantity, Net Weight and CLP

Does CLP require net weight on the label?

No. CLP requires a nominal quantity to be shown (Article 17). It does not specifically require “net weight” as a concept. It just requires the declared quantity of product.

So why do candles, wax melts and simmering granules usually show grams?

Because under UK Weights & Measures law, solid consumer products must be sold by weight.

Candles, wax melts and simmering granules are solid, prepacked consumer products, so their nominal quantity must normally be expressed as net weight in grams (g).

This requirement comes from Weights & Measures law, not CLP. 

Does the net weight have to be on the CLP panel itself?

No. Weights & Measures law requires the quantity to be shown on the product or its packaging. CLP does not require the net weight to appear inside the hazard information panel specifically.

Can I use “6 melts” or “1 snap bar” instead of grams?

That may satisfy CLP’s nominal quantity requirement on its own, but it does not automatically satisfy Weights & Measures law.

For solid products sold to consumers, quantity is normally required by weight, not by count.

So “6 melts” or “1 snap bar” on its own is usually not sufficient to cover both regulations. 

Is nominal quantity the same thing as net weight?

No. Nominal quantity means the declared amount of product. Net weight is one way of expressing that quantity for solid products.

They are related, but they are not legally the same thing for weights and measures, and clp. 

Which law do I have to follow: CLP or Weights & Measures?

Both, if your product is supplied to consumers.

CLP controls how hazards are labelled.
Weights & Measures controls how quantity is declared.

They serve different legal purposes and both apply.