ING Direct has launched a cash individual savings account (ISA) guaranteed to pay 6.55% for the first six months it is held by savers.

Following this initial period the rate reverts to a variable 5.13%, a saving and investment rate considered very favourable in the industry and putting it in contention for the best ISA on the market.

The rate offered means that savers will effectively earn a 6% annual effective rate (AER) over 12 months if they put in the maximum permitted £3,000 for the year and if they feel it is the best ISA for them.

However, savers will not be allowed to transfer existing ISA funds into the account, entailing that they will only earn the rate on this year’s ISA allowance.

The new ISA will probably put ING back in the best buy tables, a position it held back in 2003 and for three subsequent years with its well-regarded online saver account.

However, the bank slipped from view after it left the rate at 4.75% after the two recent interest rate rises imposed by the Monetary Policy Committee (MPC) at the Bank of England.

This reluctance to increase the rate it offered savers angered many account holders and the new ISA is an attempt by ING Bank to once again offer what many regard is the best ISA on the market.