Current value of damaged and destroyed capital stock is estimated at about 10% of GDP, says the development lender.
The massive earthquakes and aftershocks in February has caused an estimated $5.1 billion in direct physical damage in Syria, said the World Bank.
"The current value of the damaged and destroyed capital stock is estimated at about 10 percent of GDP," said the World Bank in its latest estimate on Friday.
"The widespread damages impacted four governorates, where around 10 million of Syria's population resides," the report said.
Millions have been left needing urgent help with accommodation and medical care.
The earthquake that struck on February 6 hit southern Türkiye and Syria, devastating scores of cities and killing more than 50,000 people in both countries.
The development lender added that its report does not cover broader economic impacts and losses for Syria, such as production or business interruption.
The most severely-hit governorate was Aleppo, with 45 percent of the estimated damages. This was followed by Idlib and Lattakia.
A subsequent earthquake on February 20 caused added damage, and continued aftershocks are likely to add to damage estimates over time, said the World Bank.
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Damages by sector
Direct damages to residential buildings account for nearly half of the total, while infrastructure damages amounted to 18 percent of the total.
Direct damages to non-residential buildings account for one third of the total impact.
"These losses compound years of destruction, suffering and hardship the people of Syria have been enduring," said Jean-Christophe Carret, World Bank country director for the Middle East department.
"The disaster will cause a decline in economic activity that will further weigh on Syria's growth prospects," he added.
The World Bank has also started a Syria Rapid Damage and Needs Assessment that will provide a more detailed sector by sector assessment and include estimates of economic losses and recovery needs.
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