The Sheffield-based firm said that after a solid start in January and February sales volumes then picked up strongly, and March and April traded ahead of management's expectations.
Performance for the year to date has been ahead of expectations. Group sales were 29 per cent up on 2020 for the four-month period. They were 4 per cent lower than the same period in 2019, and flat against 2019 in March and April.
The turnaround of its UK distribution business is "progressing well".
Customer numbers are rising and the firm is regaining market share. Based on current momentum, SIG expects the monthly growth figures vs 2019 to turn positive early in the second half.
SIG added: "Whilst the evolving Covid-19 backdrop will continue to create uncertainty in the short term, more so in our EU markets than the UK, the strong demand across territories and sectors in the first four months of the year was encouraging and gives the Board increased confidence for the full year performance.
"The momentum we have seen through March and April, together with improving visibility on the near-term order book, means that we now expect the group to deliver an underlying operating profit in the first half, returning the group to profitability earlier than expected.
"Given the prevailing macro-economic uncertainties, we retain a cautious view of the second half at this stage.
"We do however continue to expect the second half to be both profitable and cash generative, and in light of the stronger than anticipated recent performance we now expect full year revenues to be slightly ahead of prior expectations, and profits also to be higher than previously expected."
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