The retailer reported a 62.1 per cent fall in pre-tax profit to £66.8m in the year to March 31 as it was dragged down by £321.1m in costs linked to a store closure programme.
Chief executive Steve Rowe said: “At our half-year results in November I outlined the need for accelerated change at M&S.
“The first phase of our transformation plan, restoring the basics, is now well under way and the actions taken have increased the velocity of change running through our business.
“These changes come with short-term costs which are reflected in today’s results.”
The retailer’s troubled clothing arm saw like-for-like sales fall by 1.9 per cent in the year. Comparable food sales were down 0.3 per cent.
Revenue nudged up 0.7 per cent to £10.7bn.
On an adjusted basis, with costs stripped out, pre-tax profit fell 5.4 per cent to £580.9m.
“There are a number of structural issues to address and we are taking steps towards fixing these,” Mr Rowe added.
“The new organisation will largely be in place by July and the team is now tackling transforming our culture to make M&S a faster, lower cost, more commercial, more digital business.
“This is vital as we start to leverage the strength of the M&S brand and values across a family of businesses to deliver sustainable, profitable growth in three to five years.”
The results come a day after M&S said it is to close more than 100 stores by 2022 as it accelerates a transformation programme that will see thousands of jobs put at risk.
The closures will affect its clothing and home stores, which have underperformed for years.
M&S named 14 stores earmarked for closure, including in London’s Bayswater and Holloway Road, with a total of 872 employees affected.
The move is part of a five-year turnaround plan spearheaded by chairman Archie Norman and Mr Rowe.
They have been seeking to save costs through store closures and shutting distribution centres as part of a wide-ranging efficiency drive as the company’s financial performance deteriorates.