Loyalty does not pay when it comes to your financial affairs, with the 'exclusive' deals banks offer to their existing customers often falling short of those available elsewhere.
Taking the easy option by plumping for a deal that does not involve any further research or switching deals with the same bank could therefore cost you dear.
And with drastic government spending cuts and ongoing economic uncertainty affecting us all, can you afford to miss out on the best buy deals?
Kevin Mountford, head of banking at moneysupermarket.com, said: “A little effort really can go a long way and consumers could potentially give themselves a large pay rise with just a few hours’ work.
Most banks and building societies offer 'exclusive' deals of some kind to their existing customers.
Current account customers, for example, are often bombarded with advertising for linked credit cards and savings accounts offering 'preferential' rates.
But despite the clever marketing used to make these deals seem attractive, no one bank offers the best all-round deal across all the financial products you need.
Anyone using Halifax’s Reward Current Account for example, will get an excellent deal on savings products but, when it comes to personal loans, would be offered an 'exclusive' rate of 9.9% - a rate that’s far higher than the 7.6% currently on offer to new customers at Nationwide.
Meanwhile, despite Nationwide providing an excellent deal on loans, with its FlexAccount customers receiving a market-leading rate of 7.5%, the building society only offers customers of its e-savings plus account returns of 2.00%.
That’s far below the 2.99% being offered by the current market-leading easy access account, the Nationwide My Save Plus. Admittedly, you need a minimum investment of £1,000 to get this great rate, and there's only one penalty-free withdrawal a year.
But even if you don't have that amount to save, you can get 2.90% with the Post Office’s Online Saver account. And, with interest rates still down at a paltry 0.50%, getting the best rate on your savings is more important than ever.
The only way to really make sure you are getting as much bang for your buck as possible is to check rates regularly and shop around for better deals.
Luckily, that’s exactly what moneysupermarket.com is here to help you do.
“There is a misconception amongst consumers that they will get preferential deals from their current provider when taking out a new financial product,” said Kevin Mountford.
“However, a brief look across the high street banks reveals that it is very much a case of swings and roundabouts, with no single provider offering best buys across the board.
What are the best credit card deals?
However, there are some competitive existing customer credit card offers out there.
Halifax’s credit card offer for existing customers offers 0% for nine months on balance transfers, and 0% for 12 months on purchases.
Meanwhile, Nationwide gives its customers the chance to take out a Gold card offering 0% for 15 months on balance transfers, but just three months at 0% on purchases.
However, if you are looking for a balance transfer deal, Barclaycard Platinum’s 0% rate lasts for 16 months, beating the Nationwide offer.
The standard rate is the same as Nationwide’s at 16.9%, but the balance transfer fee is also slightly lower at 2.9%, versus 3% with Nationwide.
MBNA also has a Balance Transfer Card offering 16 months at 0%, with a fee of 2.9%. Its standard rate is also slightly better at 16.8%.
Anyone seeking a 0% purchases deal can also find better value on the open market.
The Tesco Clubcard Credit Card, for example, gives you 13 months at 0% on purchases, and nine months at 0% on balance transfers. With a typical rate of 16.9%, those opting for this card also benefit from Tesco’s Clubcard reward scheme.
NatWest and RBS offer supposedly preferential loan rates to their existing customers, but with a typical rate of 11.4% on amounts of between £10,000 and £25,000, they are far from market leading.
As well as the Nationwide deal mentioned above, moneysupermarket.com users with good credit profiles can also borrow between £7,500 and £14,999 through Alliance & Leicester or Santander at a typical rate of 7.6%.
Even those with less-than-perfect credit scores can benefit from rates as low as 7.6% thanks to an exclusive deal with Platinum Loans.
Where should I go for the best savings accounts?
Lloyds TSB’s e-savings account pays the bank’s existing customers 1.60%, or 2.50% on balances of £10,000 or more. But you can get 2.99% with the Nationwide My Save Plus account already mentioned or 2.90% on just £1 with the easy-access Post Office account, while Santander is also offering 2.75% on £1 and above.
As with most best-buy savings accounts at the moment, both these rates include 12-month bonuses.
But they are still a much better option than the so-called preferential deals offered by Halifax (see above) and Lloyds.
If you are prepared to lock your savings away, you can also earn 3.05% over 15 months with Northern Rock, or 3% over one year with the Post Office.
You will need to invest at least £500 to take out the Post Office account, though.
When it comes to current accounts, Santander’s Preferred In-Credit Account is the best option for anyone who rarely goes overdrawn.
It pays 5.00% on up to £2,500 and also gives new customers a £100 switching bonus. The overdraft rate on this account is high at 19.9%, however.
So if you often slip into the red the Preferred Overdraft Rate version of the account, which has a 0% arranged overdraft rate for the first 12 months, is a better choice.