LBMA Silver Good Delivery is the international standard maintained by the London Bullion Market Association that defines the physical, chemical and provenance requirements for silver bars to be acceptable for settlement in the London wholesale market. The structure of the standard mirrors that for gold but the specifications and the bar size differ.

A Good Delivery silver bar is nominally 1,000 troy ounces (approximately 31 kilograms), with an actual permitted range of roughly 750 to 1,100 troy ounces. Minimum fineness is 999.0 parts per thousand, sometimes higher for refiners that produce 999.9 standard. The bar must carry the refiner's recognised mark, a serial number, the year of pour, and the assayed fineness, and the surface finish must be acceptable for long-term vaulting (no significant pitting, no exposed slag, no bleeds from internal voids). Bars are stacked horizontally rather than upright in a vault, owing to their length and weight, and chain-of-custody documentation accompanies each bar through its life.

Only refiners on the LBMA Silver Good Delivery List may stamp bars to the standard. The list is curated by the LBMA Physical Committee and maintained against documented quality, financial solvency and Responsible Silver Guidance compliance, the silver-specific counterpart of the Responsible Gold Guidance. The Responsible Silver Guidance was issued in 2017 and substantially mirrors the gold framework with adjustments for the structural differences in the silver supply chain (in particular, the high proportion of by-product silver from base-metal refining).

For the jewellery trade, the importance of Silver Good Delivery is the same as for gold: refined casting grain and sheet sold by major refineries trace back to the same bar pool that clears in London, and a jeweller buying refined silver from an LBMA-listed silver refiner inherits the upstream due-diligence story.