No sleaze please, we're Hamiltonians.

A prominent "Welcome to Hamilton" billboard erected on State Highway 1 at the northern entrance to the city has had a makeover after it was found to be a little more racy than intended.

The image of a powerboat with the not-so-subtle name "Sleaze" features on the latest Hamilton billboard, promoting the action-packed times to be had in the town.

But the connotations of fast and loose living have prompted at least one resident to complain to the council.

Hamilton city councillors earlier this year refused to allow a sex expo at its struggling Claudelands Events Centre due to concerns about morality.

Council spokeswoman Tracy Buckland said the billboard was a "slip-up" and the offending word had now been covered up with a black vinyl patch.

"Due to an oversight in our city signage process the boat's name "Sleaze" was included on the welcome to Hamilton signage at the entrance to our city," she said.

"This sign is promoting the Bridge to Bridge waterski event in Hamilton this weekend.

"As soon as we were aware of this oversight we got the boat's name covered over, as this isn't a suitable word to have on promotional signage for our city.

"We received an approach from one member of the public who also had the same view."