Revenue jumped by up 35 per cent to $463m.
Vulcan declared an imputed 27.5 NZ cents per share interim dividend, reflecting a range outlined in its prospectus.
Managing director and chief executive Rhys Jones said Vulcan's businesses traded well in the first six months.
Sales volumes in the half were up by an overall 10 per cent, driven by a 10 per cent rise in Vulcan's steel segment and an 8 per cent increase in its metals segment.
"We remain ambitious and continue to focus on improving our high service level and product availability to meet the needs of our growing and diverse customer base," Jones said in a statement.
"To this end, Vulcan's strong first-half cash generation enables the company to further invest in our staff, working capital and processing capacity for growth, and to preserve financial flexibility for potential acquisitions and distribution of profits to shareholders," he said.
Activity levels and margins in the half were ahead of expectations, reflecting Vulcan's exposure to manufacturing, mining, agriculture, food processing, transport and construction sector in Australia and New Zealand.
The company's shares have performed strongly since their debut.
Shares in Vulcan Steel listed on the ASX at A$7.20 and last traded in Australia at A$9.30.
In New Zealand, post-result, the stock was at $10.20, up 20c from Wednesday's close, and from their $7.50 NZX debut price last November.
The ASX is Vulcan's primary listing.