Retail sales this December are forecast to rise by 4% year-on-year, with consumers expected to spend \u00a342.8bn - \u00a31.6bn more than Christmas last year.\r\n\r\n\r\n\r\nThe research - released by business advisory firm Deloitte - also found online retail sales are expected to grow by more than a fifth (21%) from 2015, with values likely to surpass \u00a37bn for the first time - a considerable increase from \u00a35.8bn last year.\r\n\r\nAs a result, December\u2019s online retail sales will account for three-quarters (74%) of total retail sales growth year-on-year. \r\n\r\nAccording to another piece of research from Deloitte, online purchasing (48%) has overtaken in-store purchasing (45%) for the first time, and this trend is expected to continue during the festive period.\r\n\r\nThe firm said retailers are likely to benefit from the fact that Christmas Day falls on a Sunday this year, meaning retailers will benefit from Christmas Eve falling on a Saturday as well as Boxing Day falling on a Monday - meaning a full-day of trading hours.\r\n\r\nIan Geddes, head of retail at Deloitte, said: \u201cRetailers can expect to receive more than a lump of coal in their stockings this Christmas. \r\n\r\n\u201cSales prospects for the golden quarter are looking good for the UK retail industry, who will feel an uplift following last year\u2019s disappointing November and December.\r\n\r\n\u201cEvents such as Black Friday and Cyber Monday have dragged forward consumers\u2019 Christmas spending into the end of November. However, there are a number of other factors present that will give a boost to retail sales over the festive period. Christmas on a Sunday will maximise the opportunity for consumers to grab a bargain in the sales that follow.\u201d\r\n\r\nHe added the value of sterling means that consumers are more likely to stay in the UK during the Christmas break, while, at the same time, tourists\u2019 buying power is greater in the luxury sector.