The amount spent by shoppers in Scotland fell 0.3% in the final quarter of 2015 and by 0.9% on an annual basis, according to the latest Retail Sales Index figures.
In contrast, the value of sales across Great Britain rose by 0.1% in the fourth quarter and by 0.1% annually.
The volume of sales in Scotland also lagged, growing just 0.6% on the previous quarter, but was up 2.2% year on year.
Sales volume across Great Britain increased 1.1% during the last three months of the year, and climbed 3.7% when compared with the same period in 2014.
David Lonsdale, director of the Scottish Retail Consortium, said: “Retail sales figures in Scotland have consistently been at a low ebb over the past few years, with retailers having to work ever harder to maintain, let alone grow, sales at a time of profound structural, economic and regulatory change for the industry.”
He added: “Responding positively to these changes and becoming more productive will require retailers to invest in new technology, a higher-skilled workforce, revamped warehouses and logistics capabilities. That is all the more challenging against a backdrop in which retail sales are weak [and] shop prices are falling.”