Country faces unwanted kitten crisis as rising number are abandoned
The Blue Cross took in 542 kittens from January to June this year, up from 487 in the same period last year and 456 in 2008.
Its 11 UK animal adoption centres were caring for more than 200 kittens, with others waiting to be housed as supply exceeded demand.
The increase may be due to the current financial worries, with some people feeling unable to shoulder the costs of caring for a litter they cannot give away.
The charity urged pet owners not to leave kittens in boxes outside adoption centres, after its Cambridge site reported two incidents in one week during last month's hot weather, resulting in overheated and traumatised animals.
Blue Cross centre manager Alan Maskell said: "There are few sounds more pitiful than the mewing of abandoned kittens, and no matter how many times it happens it always brings a lump to the throat.
"We'd always urge people to ask for help or advice rather than just dumping an animal - we never judge people for taking a responsible decision for their pet."
The charity also advised pet owners to neuter their cats from an early age to prevent unwanted births.
Blue Cross vet nurse Tamsin Durston added: "We're facing a kitten crisis across the country so it's vital that people neuter their cats now to prevent the problem getting any worse."
The charity offers subsidised neutering, funded by donations, for the pets of people on low incomes.