This 1 km summary pixel data set represents the land surface of Great Britain and Northern Ireland, classified using two classification schemas: target and aggregate classes. The target class schema comprise 21 UKCEH land cover classes based upon Biodiversity Action Plan broad habitats. The aggregate class schema comprises 10 aggregate classes that are groupings of the 21 target classes. The aggregate classes group some of the more specialised target classes into more general classes. For example, the five coastal classes in the target class are grouped into a single aggregate class. The 1km percentage products describe percentage cover for each of the 21 land cover classes for 1km x 1km pixels. These contain one band per habitat class, producing 21 images for the target class product and 10 images for the aggregate class product. The 1km dominant coverage products are based on the 1km percentage products, and describe the land cover class with the highest percentage cover for each 1km pixel. A full description of these and all UKCEH LCM2020 products are available from the LCM2020 product documentation which accompanies the data. Full details about this dataset can be found at https://doi.org/10.5285/d6f8c045-521b-476e-b0d6-b3b97715c138