The amount of registrations increased from 500,000 in December 2000 to over one million, which works out at almost one registration per minute over the course of the year.
The move is being seen as an indication of the growing acceptance of internet for conducting financial transactions.
Jim Willens, e-commerce director at Nationwide, said: "Achieving our millionth internet banking registration is a massive endorsement of Nationwide online. It also recognises the good sense behind providing a fully integrated service. We offer members a choice of access channels – both electronic and traditional – and, clearly, that is what they want."
