TESCO IS TO launch an online banking service via Tesco Personal Finance, its joint venture with the Bank of Scotland. The online bank will be linked to Tesco's existing web-based home shop-ping service, and will allow customers to check their balances and make money transfers via the site. TPF chief executive Iain Clink said the decision to move into online banking came after visitor data from the ex-isting Tesco site showed that one in ten of the site's 78,000 weekly surfers viewed the financial information pages. He said: 'It is our link with the Tesco website that gives us a big advantage: as it attracts more cus-tomers so will we - and more importantly the virtual supermarket - through brand loyalty and customer traffic, will have even lower customer acquisition costs than the real supermarket.'