Care home representatives and charities warn vulnerable people could be put at risk without more funding to increase capacity in the sector across England, which has been strained by Covid-19.
Public Health England data shows there were 11.3 care homes beds per 100 people aged 75 and over in Nottinghamshire at the end of March.
This was the lowest rate since comparable records began in 2011.
The figure includes beds in residential homes, which provide accommodation and help with things such as washing and dressing, and nursing homes, which are staffed by nurses and offer support to people with more complex needs.
The trend in Nottinghamshire was similar to that across England, where the rate also dropped to a record low of 9.6 per 100 in March, down slightly from 9.8 last year.
Martin Green, chief executive of charity Care England, said he feared the long-term capacity of the system could be ‘severely depleted’ without further funding, after years of austerity and lack of investment.
He added: “The unprecedented cost pressures leveraged by Covid-19 put the future of many care providers into question, especially when one considers the burdened nature of the care sector even prior to Covid-19.”
The group is calling for support such as the Infection Control Fund – a £600 million package announced in May to tackle the spread of the coronavirus in care homes – to be extended to help care providers get through the pandemic.
The chances of an elderly person getting a care home bed differ significantly depending on where they live.
While there were 17.8 beds per 100 over-75s in Middlesbrough, there were just 2.5 per 100 in Westminster.
Caroline Abrahams, charity director of Age UK, said a lack of funding is forcing some care homes to close their doors for good.
She said: “The resulting decline in nursing home beds is a serious concern as few alternatives exist for people who need such care apart from hospital.
“No-one wants to be in hospital unless it is strictly necessary and for older people it is particularly risky to their longer-term health and wellbeing.
"It is clearly important that we have enough residential home beds, appropriately spread around the country, so older people and families have a decent choice of nearby provision if they have decided this is the place for them.”
A Department of Health and Social Care spokesman said: "The number of care home beds remains stable and care given at home is growing, with innovation and technology allowing people to live at home for longer.
“We know there is a need for a long-term solution for social care and are looking at a range of proposals as part of our commitment to bringing forward a plan that puts the sector on a sustainable footing for the future."