The RSPCA received more than 2,000 calls about pets which were dumped outside in sub-zero temperatures and blizzards.
A spokesman said that throughout December, 2,112 calls about abandoned animals were investigated in England and Wales - an increase on 1,923 last year.
On Christmas morning, a three-month-old German Shepherd cross puppy called Eve was found abandoned in a box in an alleyway in Sheffield.
A seven-week-old kitten, named Ivy by RSPCA staff, was found wandering in the snow on December 16 in Great Ayton, near Middlesbrough. A concerned member of the public took the short-haired tabby to the RSPCA.
Six Staffordshire Bull Terrier puppies were brought to RSPCA Mallydams Wood in Sussex on December 23. At only six weeks old, the dogs should not have been parted from their mother, the spokesman for the charity said.
Between December 23 and December 27, RSPCA inspectors investigated 329 complaints about abandoned animals.
The spokesman said that on Christmas Eve, a call was answered every minute from a member of the public concerned about the welfare of an animal.
Inspector Tony Woodley said: "After all these years of trying to encourage people to not abandon their pets, it's so disheartening to see that it's still happening in droves.
"These animals are simply cast aside with little thought for their health and wellbeing. There's no excuse for such callous and heartless behaviour."
A spokesman for the charity added that hundreds of injured wild animals had extended stays at centres as the cold weather delayed their release.
Stapeley Grange Wildlife Centre in Cheshire has had the busiest winter since it opened 16 years ago. At the end of December, it was housing 90 hedgehogs, 21 buzzards, 21 common buzzards and 100 swans.
Wildlife supervisor Andrew Smith said: "This was our busiest December on record with nearly twice the usual number of admissions.
"The weather was the biggest influence.
"Large numbers of wild animals were admitted due to the snow and ice making it harder for them to feed and animals which would otherwise have been ready for release are staying longer because of the harsh conditions."
East Winch Wildlife Centre in Norfolk was caring for more than 400 creatures.
Centre secretary Ann Smith said: "We're stuffed out with 412 animals here at the moment which is unheard of at this time of year. We've never had this many hedgehogs in before."