The pledges - which include £100m from the UK - arose from an appeal launched last month for £4billion, the largest in UN history. The world body estimates half the people in Syria are now living in poverty.
Only 70% of £900m pledged at a similar meeting last year has reached UN coffers, hinting at donor fatigue with no end to the bloodshed on the horizon.
UN humanitarian chief Valerie Amos said all sides in the conflict had shown "total disregard for their responsibilities under international humanitarian and human rights law".
She decried the increasing tactic of siege warfare, while UN Secretary-General Ban Ki-moon said polio had returned to Syria and he was "especially concerned" about reports of starvation.
"Children, women, men are trapped, hungry, ill, losing hope," Baroness Amos told an international donor conference in Kuwait intended to help the UN reach its £4bn target for the crisis in 2014.
Kuwait's ruling emir, Sheikh Sabah al-Ahmed al-Sabah, promised £305m in fresh assistance, while the US announced a contribution of £230m.
Qatar and Saudi Arabia pledged £35m each and the EU promised £135m.
Peace talks on Syria are due to start in Switzerland on January 22.