THE high-street banks have been accused of fleecing their customers by craftily raising credit-card costs at a time of year when people are feeling most overstretched.

Millions of NatWest and Royal Bank of Scotland customers are set for a new year shock as the banks prepare to slash the interest-free period available on many of their cards. Many people will find that they have only days to pay off their Christmas debts rather than the weeks they previously had.

This comes at a time when savings rates on some accounts are being cut savagely. Broadband firms, energy suppliers and phone companies are also after a bigger share of your hard-earned cash.

Here we suggest the best ways to avoid the profit-making traps that lie in wait in the new year.

Credit cards
Some of Britain’s biggest banks have slashed the amount of time customers will get to pay off their Christmas credit-card bills. From Wednesday, Royal Bank of Scotland, NatWest and Mint credit cards have cut the time balances can be paid off interest free from 56 days to 45 days.

The new rules mean that millions of customers will in effect have just 15 days after a credit-card bill is issued to clear their balances before they are hit by interest charges and late-payment fees.

Several of the big card firms have also raised interest rates far more than Bank rate over the past year, adding pressure to overstretched households.

American Express is one of the worst offenders, according to Moneyfacts, a data firm. The rate on purchases with the Amex Red card has gone up from 12.9% to 16.9% in the past year, while the same rate on Amex Nectar has been raised three percentage points to 15.9%. Bank rate is up just 0.5% since the year began.

In addition, lenders are slashing borrowing limits, even for customers with good repayment records, as the institutions try to protect themselves from potential exposure to bad debts.

If you are unhappy with the way you are being treated, the best deal for balance transfers is from Virgin Money. It offers 0% for 15 months, although there is a 2.98% transfer fee. At the end of the 15 months it charges a typical rate of 15.9%.

Savings
Savings rates on some leading accounts have been cut by far more than Bank rate over the past month, as banks look to claw back profits which have been squeezed by the global credit crisis.

The Bank of England reduced base rate by 0.25 points to 5.5% earlier this month, but Bradford & Bingley took the opportunity to cut the rate on some of its accounts by 0.4 points. Sainsbury’s bank slashed the rate on its savings account by 0.35 points.

Many other banks have dropped their rates by the full 0.25 percentage points, but savers are being warned to watch out for a second round of cuts in the new year.

The best variable rate deal is from the AA with a rate of 6.5% on a minimum balance of £500, although this includes a 0.2% bonus for six months. Heritable Bank has an easy-access bonus-free account paying 6.46% on balances of more than £1,000.

You can get a better deal if you are prepared to tie up your money for a year. The best one-year bond from London Scottish Bank pays 6.85%.

Phones, TV and broadband
Ofcom, the telecommunications regulator, warned last week that consumers are being misled by “hidden” charges levied by phone and broadband companies. The watchdog said it has seen a surge in complaints from customers angered by unexpected charges and has promised to launch an investigation early next year.

Some of the ploys to watch out for include extra charges to receive an itemised paper bill, fees for late payments and premium rates charged on technical helplines.

The best way to save money is to go for a bundled deal for your home TV, phone and broadband. Buying separately could add £20 or more to your monthly bill.

Aamir Baloch of the comparison firm, Firsthelpline, said: “If you haven’t got a bundled deal yet, it is worth calling your providers to see if they can offer something better, especially if you’ve been with them for overa year.”

One of the best deals is from Tiscali, which charges £25 a month - £300 a year. It includes 60 channels of TV, up to 8MB (megabytes) broadband and free evening landline calls.

If you want a more comprehensive package, Sky offers one of the best deals for £71 a month. This includes all the premium movie and sports channels as well as up to 16MB broadband and free evening and weekend landline calls.

Mobile phones
Although the Apple iPhone may have been on many Christmas lists, it is one of the worst mobile packages in Britain in terms of value for money, according to mobile experts at the comparison site, Moneysupermarket.

The handset, which can only be purchased through O2, requires customers to sign up to an 18-month contract costing at least £35 a month. There is also an upfront charge of £269 for the phone itself.

For this you get 200 free calls and texts. A much better deal is 3’s Mix and Match tariff, which costs £15 a month (£180 a year). It offers 300 minutes of calls which can also be used as texts - 150 texts and 150 free calls, for example. You get a free handset.

Energy
Npower customers on its tracker deal face a 17% increase in their bills for gas and 13% for electricity on Wednesday.

It follows a similar move by British Gas, and more energy suppliers are expected to increase their rates in the new year.

If you want to protect yourself, the best fixed deal is Scottish Power’s Online Price Fall, which costs on average £788 a year.

However, the cheapest deal overall is British Gas’s online Click Energy 4 tariff, costing on average £734 - £226 less than the average standard deal.