Companies are quietly confident as expected economic growth slows somewhat.

Annual GDP growth is expected to be around 3 percent this year.

That's led to businesses paring back their optimism in the Quarterly Survey of Business Opinions.

NZIER senior economist Christina Leung says businesses are looking for sustainability, rather than the explosive growth they expected last year.

"While activity has not lived up quite to those lofty expectations, we are still seeing activity at solid levels."

Seasonally-adjusted optimism is sitting at 20 percent of businesses in the survey.