World Bar, in Kings Cross, will now serve last drinks at 3.30am instead of 3am, and will close the venue to new revellers at 2am rather than 1.30am.

It is the first bar to be approved for extended trading in the suburb, which has seen a significant drop in revenue and foot traffic since the restrictions were put in place.

Iconic gay bar Stonewall, on Oxford Street, has also been approved for the later trading hours.

Minister for Racing, Paul Toole, is set to announce the longer hours on Friday.

"The later closing time for Stonewall has been approved in time for the 2017 Mardi Gras," Mr Toole said in a statement.

"Stonewall and World Bar demonstrated a genuine orientation towards live entertainment. Live entertainment helps provide more diverse nightlife options."

Since the laws were relaxed as part of a two-year trial, three other bars - The Palace Hotel, ArtHouse Hotel and the Observer Hotel - have also had extensions approved.

Under the trial, venues in the CBD and Kings Cross that offer live entertainment can apply for a later 2am lockout, and last drinks at 3.30am.

Liquor & Gaming NSW is assessing another 15 applications for longer hours from other venues.

"I'm pleased there has been such a strong response from the industry to our government's relaxation of lockout laws," Mr Toole said.

As part of the change, bottle shop trading hours and home delivery of alcohol - which previously ceased at 10pm - will continue until 11pm.

Small bars are also able to have 100 patrons instead of 60.

The changes to lockout laws were announced by former NSW premier Mike Baird last year, three months after former High Court judge Ian Callinan recommended the changes to the government.

The changes began in January. It is the first major review of the laws since they were introduced in early 2014.