Police across the motu will observe a minute's silence in honour of the Nelson police officer killed on New Year's Day.
Fleming died after being struck by a vehicle while patrolling in Buxton Square early on New Year's Day.
Her funeral will be held on Thursday 16 January from 1pm at Nelson's Trafalgar Centre.
The service will include a motorcade, honour guard, police piper, a flag presentation to Fleming's family, and it will be livestreamed.
Prime Minister Christopher Luxon was cutting his trip to the United Arab Emirates (UAE) short to return to New Zealand in time for the funeral.
Luxon flys out Monday morning to witness the signing of the UAE trade deal, but has cut the trip in half because it was important to him to be back in New Zealand in time for Senior Sergeant Lyn Fleming's funeral on Thursday.
Police Commissioner Richard Chambers said a minute silence would be observed at 1pm on Wednesday, marking 24 hours before her funeral service.
"We have invited staff to pause and observe a minute's silence wherever they are to remember the ultimate sacrifice of one of our own and reflect as we prepare to lay Lyn to rest," he said.
All police flags would remain at half-mast until Friday.
Flags will fly at half mast across government and public buildings on that day as a mark of respect.
Sign up for Ngā Pitopito Kōrero, a daily newsletter curated by our editors and delivered straight to your inbox every weekday.