The charity said the "substandard care" will result in 50,000 people nationally being forced into care homes early, costing £70m for each avoidable month people with dementia spend in care.
Charity bosses are calling on commissioners to invest in dementia services and training to keep more people out of hospitals and care homes and to save the NHS and councils from bankruptcy.
Nicki Dyson, Alzheimer's Society Yorkshire and Humber area manager, said: "It is an absolute travesty that so many people with dementia are being forced to struggle without the care and support they need. The consequences of this represnt an unacceptable human and financial cost.
"Half a million people with dementia live in the community and many will need help with everyday tasks such as eating meals, washing or going to the toilet.
"This help not only maintains dignity but prevents serious health issues. While staying at home is not right for everyone we know many people want to remain in the familiar surroundings they are used to with family or loved ones. Only with the right support will this be possible."
SOURCE: The Halifax Courier, UK
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