Lead restriction in the jewellery context refers to the regulatory ceilings on lead content imposed by the European Union and the United States, which limit how much lead can be present in a finished jewellery item sold to consumers. The two regimes have different scopes and different limits, and a piece of jewellery sold internationally must comply with the stricter of the two for any given component.

In the European Union, lead in consumer jewellery is regulated under REACH (Regulation (EC) No 1907/2006), Annex XVII, entry 63. The general limit is 0.05 percent by weight in any individual part of a jewellery article, with specific exemptions for certain crystal glass products and for vintage and antique items placed on the market before October 2013. The limit applies to the metal alloy as well as to glass, plastic, paint and surface coatings.

In the United States, lead in children's jewellery is regulated by the Consumer Product Safety Improvement Act (CPSIA, 2008), with limits of 100 parts per million (0.01 percent) total lead in any accessible component. State-level regulation applies to adult jewellery in some jurisdictions, most notably California's Proposition 65, which requires warning labelling for any jewellery sold in California containing more than 0.06 percent lead by weight in metal components, with stricter limits for surface coatings and for jewellery intended for children.

For the working trade these restrictions matter for two principal reasons. First, lead-glass-filled ruby and certain other composite-treated stones contain substantial proportions of lead, and selling such a stone in a setting marketed for children in the United States is a CPSIA violation; AGTA and the major laboratories have been explicit on this point since 2010. Second, certain low-melting-temperature solders and base-metal alloys used in costume jewellery contain lead, and a jeweller importing these from non-compliant supply chains is on the hook for testing and compliance under both regimes.