Anchor Trust has acquired 24 care homes from LNT Group, in a deal worth more than £100m.
The homes, in the north and midlands, provide a total of 1,317 en-suite rooms for older people, including older people with dementia.
Anchor has also made the acquisition of the Cavendish Healthcare Group.
The five residential care homes operated by Cavendish in Essex and Suffolk bring the total number of care homes operated by Anchor to 119. They provide a total of 307 additional rooms for older people, including older people with dementia.
Anchor also runs 18 specialist mental health facilities including independent hospitals, residential facilities which support community living, and specialist facilities.