Ageing Pinjarra residents can access care close to home after the opening of another 25 beds at Bedingfeld Park.
The new dementia wing is an expansion of the original 45 beds, taking the accommodation's care capacity to 70 beds.
"It's a memory support unit so it's a secure environment," chief executive Debra Mcleod said.
"We are the only aged care centre in Pinjarra so it's wonderful that we've been able to expand to support the need.
"A lot of residents are currently being cared for in their homes but you can't look after someone with dementia in a home very successfully.
"It means residents who need to have residential aged care can now stay in Pinjarra."
She said the new wing would be named Wallace House in honour of Dr Peter Wallace for his long-standing contribution to Bedingfeld Park.
Designed for people aged over 65 years living with dementia and requiring a high level of nursing care, the new single rooms include an ensuite bathroom and robe area.
The new wing also incorporates a nurse's station, common living, dining and activities areas, treatment and utility rooms, a servery kitchen, a secured landscaped courtyard and areas for staff training and support services such as physiotherapy.
The project supported 48 jobs during construction and is expected to create 18 ongoing jobs in Pinjarra.
It was funded by $3.5 million from the federal government, $2 million from the state government and $1.5 million from Bedingfeld Park.
Canning MP Andrew Hastie said the expansion means more elderly residents will be able to receive the care they need locally and remain close to their families.
"It is so important that we expand and improve health services in the Peel region," Mr Hastie said.
"That's why the federal government committed to this project back in 2018. I know it's going to make a big difference for many families in our community."
Deputy Prime Minister Michael McCormack said the project would also help bring economic prosperity to Pinjarra for many years to come.
Murray-Wellington MP Robyn Clarke said the expansion would help local Pinjarra residents stay in the community as they age.
"The naming of the new wing, Wallace House, honours Dr Peter Wallace for his long-standing contribution to Bedingfeld Park as both a doctor and Board member," she said.
Regional Development Minister Alannah MacTiernan said the new wing would allow Bedingfeld to meet more of the demand for aged care services with increased quality for senior residents in the Peel.
"Quality aged care accommodation helps Western Australians to remain living in their local communities, which benefits local jobs, local business and helps to keep our regional communities strong," Ms MacTiernan said.
Bedingfeld Park is a community-owned non profit residential aged care facility successfully operating since 1983.