Patrons will be locked out of Newtown bars from 3am on weekends after publicans agreed to trial a suite of self-imposed restrictions designed to ward off late-night revellers and improve safety in the precinct.

Late-trading venues in the Newtown and Enmore area will be closed to new patrons after 3am, while customers already in the venue before 3am will require a "pass out" if they wish to re-enter the premises.

Bars including the Marlborough Hotel, Zanzibar and The Bank will also ban shots and "doubles" after midnight – a regulation that has been implemented in Kings Cross and the CBD – and cease sales of alcohol 30 minutes before closing.

About 10 venues signed up to the agreement at a meeting on Friday, which includes almost all late-trading establishments in the precinct. Only one, the Sly Fox in Enmore, has declined to join the accord. The troubled Imperial Hotel in Erskineville is currently closed and was not included in the discussions.

The six-month trial is due to begin on September 1. It will apply on Friday and Saturday nights, but not during the week, when trade is generally quieter.

Newtown Liquor Accord chairman Tim Claydon said the agreement aimed to deter revellers from heading to King Street or Enmore Road once 1.30am lockout and 3am "last drinks" kicked in around the CBD, Oxford Street and Kings Cross.

"We're not going to be the last spot for drinks," he said. "Don't even think of heading to Newtown at 3am after a night out in the city, as you simply won't get into venues."

Anecdotal reports have suggested more partygoers are frequenting Newtown since the city lockouts were introduced in February last year and Mr Claydon noted "there seems to have been an increase in patronage in the area".

Crime statistics show on-premises alcohol-related assaults in Newtown increased in the 12 months to March, but overall, alcohol-related violence in the area is stable. A recent Bureau of Crime Statistics and Research report said there was "little evidence" the lockouts had shifted violence to surrounding areas.

The lockout laws were passed to combat alcohol-fuelled violence following the deaths of Thomas Kelly and Daniel Christie. Mr Kelly's father, Ralph Kelly, founder of the Thomas Kelly Youth Foundation, said the announcement was "great news" and he congratulated venues on takingthe initiative.

"It's great to see the industry itself wanting to do something," he said. "We're all on the same side. We want people to be safe, we want people to have a fun night out."

The state government is due to review the lockout and associated measures in February, and some groups have pushed for the regime to be expanded. Mr Claydon denied the self-imposed restrictions in Newtown were an attempt to ward off further government regulation.

"It's not really that," he said. "We thought 3am was a good time for Newtown, for our area."

Tyson Koh, spokesman for Keep Sydney Open, said the changes were reasonable, because the lockout had "shifted the landscape" of Sydney's nightlife towards Newtown and Enmore.

"It's become necessary, but it's as a result of the lockouts," he said.

The Australian Hotels Association also welcomed the development. NSW director of liquor and policing John Green said the package had been developed by local hoteliers and police and was "the right model for Newtown".