Overall operating conditions for local firms continued to improve last month, according to a survey out yesterday.
The Nikkei Singapore purchasing managers' index (PMI) came in at 51.4, up from 50.8 in August. A reading above 50 signals growth.
Unlike the official PMI, which covers only manufacturing firms, the Nikkei measure is based on data compiled from monthly questionnaires to executives in around 400 private-sector companies.
They are selected to represent the structure of the economy and include manufacturing, services, construction and retail sectors.
The expansion in output recorded for September was the strongest pace of improvement posted since February. It was due to "new product launches, promotional activities and the initiation of new projects", said Markit, the financial information services provider which compiled the survey.
But the report also found that total new work remained unchanged for the second successive month, which means that new order intakes have now been stagnant or near-stagnant since June.
"The headline PMI signalled the strongest improvement in Singapore private-sector operating conditions for seven months in September, with companies reporting a further solid increase in output as they geared up for new projects and promotions," noted Ms Annabel Fiddes, an economist at Markit.
"However, client demand failed to show any signs of meaningful improvement, with total new work stagnating for the second month in a row while new export business rose only slightly.
"This could translate into weaker growth of output as we head into the final quarter of 2015, with slower global growth also weighing on the overall business outlook."
The official PMI, which is compiled by the Singapore Institute of Purchasing and Materials Management (SIPMM), was released last Thursday and showed a further contraction in factory activity as restructuring, higher costs and tepid global demand continue to bite.
The reading fell to 48.6 last month from 49.3 in August.
The Nikkei Singapore PMI report also found that companies saw a further increase in total costs during September, with the rate of inflation rising to a seven-month high.
Data indicated that a renewed rise in purchasing prices, along with the fastest increase in staffing costs since November last year, had contributed to greater overall input prices.