Masks were reintroduced indoors in settings including hospitality venues, retail stores and workplaces. Masks are not required while sitting, eating or drinking in a hospitality setting.

Several pubs, bars and clubs - such as Assembly The People's Pub, Hopscotch, Mooseheads and Cube - have been added as close or casual exposure sites on the ACT Health website.

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Venue manager at Hippo Co. in the city Eamon Rooney said customers had started voluntarily putting on masks on Tuesday. He said he hadn't seen a decline in bookings since the mandate came into force.

"We still have less than 50 per cent capacity, so we're always at that capacity. It's hard to tell whether or not business would have been affected from a full capacity standpoint, but it's been pretty normal for us," he said.

"Thursday, Friday, Saturday, we're pretty much fully booked through the week."

Bartender at Dolly's in the city, Jessica Tonkin, also said some customers were already putting on masks before the mandate. She said the restaurant might have more people coming through because they felt safer.

"I don't think it stops people from coming out at all. I think honestly people are more comfortable, especially with all the Omicron cases, to wear a mask. People were wearing masks before just by themselves," she said.

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On Tuesday, Australian Hotels Association General Manager Anthony Brierley said the ACT should follow Queensland's lead in exempting the hospitality business from indoor mask mandates.

"If [the ACT government] want to do this sort of stuff, they've got to have the data to be able to justify it. At the moment they're just licking their finger and sticking it up in the air and expecting hospitality businesses to kick the can for their unnecessary public health restrictions," he said.

The AHA general manager said Canberrans would avoid going out and instead gather at home.

"The worst part about the hypocrisy is that this mandate doesn't apply to residential homes," he said.

"We're still going to have super spreader events, [but] there's going to be no contact tracing because you can't use a QR code at someone's house. There's no COVID safety measures that we would ordinarily have in a pub and we haven't changed people's behaviour."

At a press conference on Wednesday, ACT Health Minister Rachel Stephens-Smith said there was a "mixed response" to the mask mandate from the hospitality and retail industries.

"We're in a different situation now than we were when we first introduced a mask mandate in retail and hospitality settings," she said.

"[The first time Canberrans] saw it as a really significant signal about the increased risk that we thought we were facing from the outbreak in New South Wales at that time.

"This time, people are used to wearing masks; they understand that it's a relatively minor inconvenience."

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