Venues and Events Whangarei manager John Lynch is encouraging local businesses to prepare for the onslaught, which he "guesstimates" at more than 5000 visitors alone for the Four Nations test match between the Kiwis and Samoa.
"We should all be trying to put our best foot forward from a customer service point of view. It's a massive day for the city."
Council figures suggest the match would inject $3.8 million into the local economy, Mr Lynch said.
"I know there's absolutely bus-loads of people coming up from Auckland and we've got two league teams in town for a whole week - that's seven nights' accommodation and three meals a day."
One business opening its doors especially for the bumper Saturday is The Walton St Cafe. Normally trading weekdays, the cafe will be open from 7am on Saturday for coffee and a "parade-friendly" breakfast menu, co-owner Matt Brown said. "We're celebrating the 50th anniversary and this is a great opportunity for folks who don't get to come down during the week to come and try us. We're hoping for a cracker of a weekend."
The 1960s themed parade, with more than 70 floats and 135 vehicles from a variety of local groups and organisations, will travel down Walton St from 10am on Saturday, finishing at the Town Basin.
Gates open to the Four Nations rugby league test at Toll Stadium at 1.15pm, with pre-match entertainment starting at 3pm and kick-off at 4pm.