The UN refugee agency says most Syrians are back in Aleppo, Hama, Homs and Damascus. UNHCR's Andrej Mahecic says the displaced want to find out what happened to their families and check on their properties.
Nearly half a million Syrians have returned to their homes so far this year, including 440,000 internally displaced people and more than 31,000 returning from neighbouring countries, the UN refugee agency said on Friday.
Most returned to Aleppo, Hama, Homs and Damascus, it said, on the view that security had improved in parts of the country.
"This is a significant trend and a significant number," UNHCR spokesman Andrej Mahecic told a Geneva news briefing.
"Most of these people are returning to check on properties, to find out about family members ... They have their own perceptions about the security situation, real or perceived improvements in areas they are returning to."
He said it was premature to say whether de-escalation zones set up via talks held by Russia, Iran and Turkey in Astana or UN-led peace talks in Geneva had accelerated the return trend.
An estimated 6.3 million people remain internally displaced across Syria after more than six years of war, Mahecic said.
A further 5 million are refugees in neighbouring countries.
A survey conducted by the UNHCR in recent weeks showed that more than 80 percent of Syrian refugees expressed their wish to return home, he said.
"Of those, only about 6 percent were considering that to be a possibility in the near future," he said
UNHCR believes that conditions for refugees to return in safety and dignity "are not yet in place in Syria", he added.
Syria's conflict broke out with anti-government protests in 2011, but has since evolved into a multi-front war that has killed more than 320,000 people.