The World of WearableArt injects more than $20 million into the Wellington economy, the latest figures show.
A new assessment of the impact of the event on the capital has found more people are travelling from out of town to attend the event, and they're spending up while they're there.
Last year's two-week season brought in $21.6m, the latest economic impact assessment by Wellington City Council has found.
That's an increase of about 50 per cent since the last assessment in 2009, when the annual value of the event was put at $15.1m.
When the show first came to Wellington in 2005, it brought $8m to the city.
WoW attracts 47,000 people a year - an amount expected to grow by 8000 this year with the season being extended to include a third weekend.
Last year, 71.6 per cent of visitors were non-Wellingtonians, compared with 65 per cent in 2009.
Wellington Mayor Celia Wade-Brown said the economic growth showed the value to the city of the event, which is subsidised by ratepayers. The amount has never been made public.
"WoW also showcases originality in costume, dance and music," she said. "Being home to this new art form is a boost for the creative events capital."
Kirkcaldie & Stains managing director John Milford, who last week criticised the council for failing to do enough to boost the city's economy, said WoW was critical to the city, and it needed two or three similar events.
"WoW is a complete event and it seems to benefit all of us . . . we need more and we need more of the same calibre."
Positively Wellington Tourism chief executive David Perks said the economic value was helped by the fact WoW ran for two weeks, meaning a sustained increase in retail and hospitality trading.
"WoW is almost better than Christmas in terms of sustained spending over a period of time and people buying high-value items."
WoW chief executive Megan Matthews said the growth was a reflection of people coming back year after year, and often the biggest challenge was getting people to attend for the first time.
"Once they come for that first time, they're hooked and they come back. And when they come back, they come with friends."
Ange Harris, 39, an Ashburton nurse, is already booked in for her fifth show this year. The event doubles as a girls' get-together for her mother and four sisters who travel from Perth, Christchurch and Ashburton for a weekend.
While they had contemplated doing something different, nothing compared to the value of a WoW weekend, Ms Harris said.
As well as the show, which was "different every year", shopping, food and wine were high on the agenda, she said. "We just treat ourselves."
- The Dominion Post