An Essex rescue charity believes the number of abandoned and neglected horses has risen because of an increase in the cost of hay and fuel.
The Remus Memorial Horse Sanctuary in Buttsbury can home 68 horses, but has been "full to bursting" for months.
Founder Sue Barton believed economic pressures were the main reason for people giving up their animals.
"Petrol has gone up, hay has gone up, food's gone up, literally everything that we need has gone up," she said.
"The cost of having a manure heap has gone up, rubbish to be collected has gone up, everything."
Among the causes of concern is the the price of hay, which has almost doubled in price from last year, and the cost of veterinary bills.
Ms Barton, who set up the sanctuary 28-years-ago, said with it was a worrying time for her and her team.
"Our donations are down by 40% this year, so that's a significant hit when everything else is going up," she told BBC Essex.
"Trying to keep our heads under water is very difficult at the moment."
"We're very worried, especially during the winter months, which are always the hardest and most expensive time.
"We want to try and help these animals, but there's only so much we can do."
Richard Wright of Clacton-based merchant Hay & Straw Ltd sells 90% of his hay stocks to Essex horse owners.
He said the current price for a bail of hay started at £6, but could go up to £10, whereas a year ago he would have charged between £2 and £5.
This, he said, was down to last year's very dry, then wet summer, as well as increases in farmers' running costs such as fuel and fertiliser.
"Although the weather was good it was too good for the grass and the hay season, so we didn't get the crop that was required, it was something like 50% down," he said.
This shortfall has led to some people having to import hay, from as far afield as Pakistan.
Mr Wright believed the current situation was at its worst.
"It's got to a price where it's got to settle down," he said.
"I can't really see it being any more than where it is now, because it's just ridiculous to see this price as it is now."