A total of 3.2 million are anxious, as Shelter has seen an increasing number logging onto its website looking for advice on rent and arrears.
Three in five (59%) rent or mortgage payers said they are already struggling to keep up with housing costs in the winter months.
Worryingly more than a quarter (26%) admit they would feel too ashamed to ask for help when struggling with housing payments.
Nadeem Khan, Shelter’s helpline adviser, said: “Every day at Shelter we hear from people who are feeling overwhelmed by mounting rent or mortgage bills, as the increasing pressure of sky high housing costs continues to take its toll.
“Many have spent a long time thinking they have nowhere to turn and are often close to breaking point by the time they come to us. If you’re in this situation, it’s so important to remember you’re not alone and that help is available.
“We all understand how tempting it is to bury your head in the sand, but advice from Shelter is only a click or a phone call away – so get advice early to prevent things from spiralling out of control.”
Shelter’s study follows Legal & General Mortgage Club’s Mortgage Mood survey, which revealed that a third of mortgage holders would not be able to afford mortgage repayments if they increased between £100 and £199.
Two thirds (63%) of homeowners expect interest rates to rise in 2015, yet just a third (35%) are preparing properly, as a quarter (23%) plan to wait until the first rate rise before reacting.
Over a quarter of (27%) said speaking to a broker would encourage them to review their finances.
Jeremy Duncombe, director at Legal & General Mortgage Club, said: “Our latest Mortgage Mood data suggests that many borrowers are not ready for an interest rate rise.
“The last time rates went up in the UK was in 2007 and although the base rate has been static at 0.5% for over five years, they will rise sooner rather than later.
”Waiting for rates to rise before you act might seem like a good idea to some but in reality the best deals won’t be available once rates have risen as lenders price in a rate increase well in advance.”