MYOB's James Scollay said businesses with an online presence were also more likely to take on new workers.
While 16 per cent of SMEs with a website were planning to increase their full-time staff this year, only 6 per cent without had the same intentions.
Scollay said a "digital divide" was emerging in the New Zealand economy.
"Businesses with an online presence reach more people and become more engaged with their customers. They also earn more, have more work in the pipeline, and are more likely to be hiring staff," he said.
The overall proportion of SMEs with a website was still concerning - less than 50 per cent - but Scollay said he was encouraged to see it increasing.
From 34 per cent six months ago, the proportion with a website has now risen to 38 per cent. Only 14 per cent had both a social media site and a website, and 3 per cent said they were unsure what online presence they had.
In June last year, Westpac and MYOB combined to offer businesses free website development, with the goal of getting 10,000 businesses online.
Scollay said that venture may have contributed to the 4 per cent increase in SMEs that now had a website.
The biggest barrier to developing a website was now one of attitude rather than time or access to technology, he said.
The latest survey found 35 per cent of SME operators without a website did not see the value of a website, and another 23 per cent said it was not a priority.
"Previously we've seen concerns around cost and access to technology as being the barriers. I think it's a positive change and now we need to make the importance of making the change clear and it will rise up on the priority list," Scollay said.
MYOB - which claims a New Zealand market share of between 60 and 70 per cent - found the proportion of SMEs using cloud-based technology has also lifted in the last six months, to 18 per cent.
The most popular social media platform for SMEs was LinkedIn, ahead of Facebook, Google+, Twitter and YouTube.
The MYOB Business Monitor was carried out by Colmar Brunton in August.