> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/buildings-and-infrastructure-portfolio/os-mastermap-topography-layer-building-height-attribute/release-notes.md).

# Release Notes

## [OS MasterMap Topography Layer – Building Height Attribute – April 2026 release note](/os-downloads/products/buildings-and-infrastructure-portfolio/os-mastermap-topography-layer-building-height-attribute/release-notes/april-2026.md)

This release note provides information about the April 2026 release of OS MasterMap Topography Layer – Building Height Attribute product.

## [OS MasterMap Topography Layer – Building Height Attribute – October 2025 release note](/os-downloads/products/buildings-and-infrastructure-portfolio/os-mastermap-topography-layer-building-height-attribute/release-notes/october-2025.md)

This release note provides information about the October 2025 release of OS MasterMap Topography Layer – Building Height Attribute product.


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