The new tally brings to 50,325 the total number of deaths caused by the disaster across both countries.
A total of 5,951 people were killed across Syria, while Turkey recorded 44,374 deaths after the February 6 earthquake.
The Syrian government said 1,414 people had been killed in areas under its control, while Turkish-backed officials in Syria have put the death toll at 4,537 throughout rebel-held areas of the country.
The toll in areas outside government control includes deaths in territory held by rival rebel groups.
Local authorities relied on data collected from hospitals, medical centers and civil defense in Idlib and northern Aleppo province, health official Maram al-Sheikh told AFP.
They also included civilian sources, he said, many of whom buried their dead without taking them to hospital.
The toll was finalized with help from the Assistance Coordination Unit (ACU) organization, a local United Nations partner.
The UN said it relied on the ACU's data, including death tolls, which match those of the Turkish-backed authorities.
The death toll in rebel areas was "almost final, since most victims have been pulled from under the rubble", he said.
AFP had previously reported 3,688 deaths across Syria.
The quake came nearly 12 years into Syria's civil war, which devastated swathes of the country, killed nearly half a million people and displaced millions more.