Only one in three people plans their finances more than a year ahead, according to research from Citizens Advice.
The charity, which is encouraging people to get on top of money matters for the new year, found that just 31% of people surveyed are thinking about their finances more than a year into the future.
The survey of more than 2,000 people also found that in the last two years, one in three (32%) people had not personally checked if they were on the best mobile phone contract, while 33% had not checked if they had the most appropriate energy tariff and 34% had not looked at whether they were on the best broadband deal.
Citizens Advice said that in the last 12 months it has helped with 1.8 million queries about debt and personal finances.
It is encouraging people to get their finances in order for the year ahead by reviewing where they can make savings and getting on top of any debts.
Gillian Guy, chief executive of Citizens Advice, said: "Planning your finances ahead can keep you in the black.
"Looking at how you spend your money and where you can trim back will help you plan a budget that meets your daily costs. It can also help you build up savings so that you're prepared for any sudden changes, from one-off expenses like replacing a washing machine to a change in your employment.
"It's also important to shop around so you get the best deal on your household bills. Energy, broadband and mobile phone tariffs all vary widely, and paying over the odds for lots of bills can all add up."
Citizens Advice suggested that in order to carry out a "financial health check", people should take steps such as getting a clear idea of their budget and putting dates for when contracts for services like mobile phones and broadband are due to end in a diary, as a reminder to shop around for a better deal.
People with debts should make a clear list of their creditors, how much they owe and when they need to pay it back, it said. If it is impossible to pay all the debts off, Citizens Advice can help with information on which debts should take priority and negotiating with creditors.
Meanwhile, the British Bankers' Association (BBA) has suggested five tips to help people improve their finances:
:: Prepare for a rate rise. Many experts expect 2016 to be the year when interest rates finally start going up a little. It is worth thinking about whether you are prepared if repayments on borrowings like your mortgage start to rise. Consider how you might accommodate a rate rise and factor it into your budgeting. Many banks offer a mortgage repayments calculator that can help you plan ahead.
:: Manage your money on the move. Some banks offer text and email services to help you keep an eye on your account while on the move.
:: Create a "rainy day" fund. An emergency fund should lessen the chances of you having to rely on your overdraft if the boiler or car breaks down.
:: Consider paying by direct debit. Paying your regular bills by direct debit allows you to spread costs over an extended period. Some businesses also offer discounts for you paying by this method.
:: Shop around. The current account switch service moves all your regular debits and credits for you so that if you do fancy trying a new provider, you can do it quickly and easily. More than two million people have switched since the service began in 2013.