Person-to-person mobile payments service Paym will be rolled out by Britain's banks at the end of this month.
From today, customers of participating banks and building societies can register their mobile numbers, linking them to their current accounts, for the service ahead of its 29 April launch.
Built under the Payments Council umbrella, Paym - pronounced pay-em - will allow registered users to make person-to-person and person-to-business payments from within their bank's app by simply using a mobile phone number as a proxy, without the need to disclose their sort code and account number.
Customers of Bank of Scotland, Barclays, Cumberland Building Society, Halifax, HSBC, Lloyds Bank, Santander and TSB can register from today. Clydesdale Bank, first direct, Isle of Man Bank, NatWest, RBS, and Yorkshire Bank will follow later this year.
Research commissioned by the Payments Council suggests that the service could prove popular with Brits, who tot up an average of £255.81 each year in IOUs and other informal loans to each other, reaching a total value of £12.6 billion.
People are most likely to turn to their family for a small advance. More than half of IOUs are between family members, with the bank of mum and dad accounting for £3.7 billion per year, or 30% of the total. These loans tend to be for specific practical purposes, such as helping out with bills, household costs and debt.
Adrian Kamellard, chief executive, Payments Council, says: "Our IOU research suggests that every adult in the UK is lending just under £5 per week to someone they know. Small sums like this soon add up so it's great that Paym will give people a new option of quickly and securely paying someone back - whether it's for lunch, a train ticket or just a cup of tea."