MILLIONS of customers with Royal Bank of Scotland (RBS) face new fees of up to £72 a year from this week for dipping into their arranged overdrafts.

From Friday, current account customers will be charged a £6 a month "arranged overdraft usage fee" when they go over £10 into the red, on top of annual interest of 19.89%.

The changes also mean the interest-free "buffer" on arranged overdrafts will be cut from £100 to £10. The move brings the bank into line with other big high street names, including Lloyds TSB, Santander and Halifax.

Select and Select Silver customers with arranged overdrafts will be affected by the RBS changes. These customer numbers are understood to be in the low millions, although not all of these use their overdraft.

Student and graduate accounts will not be affected by the charges, nor will some paid-for "packaged" accounts such as the Select Platinum Account, Advantage and Royalties Gold Accounts and Black Account.

It comes at a time when the average authorised overdraft rate on offer is at a new high, according to financial information website Moneyfacts. The typical overdraft rate has crept up to 16.02% –the highest rate on Moneyfacts' records going back six and a half years. A year ago, authorised overdrafts charged an average 15.41%.

Rachel Springall, spokeswoman for Moneyfacts, saidRBS customers who are overdrawn for large chunks of the month will find the £6 fee "less painful" than those who tip slightly over the £10 buffer for a couple of days.

Consumers could consider First Direct, which offers a fee-free overdraft on the first £250 and a 15.9% rate for the rest of the balance, she said.