Labour was handed more than £2.4 million by trade unions in the second quarter of the year.
But the party still raked in less in sizeable gifts than the Conservatives, by £4,116,006 to £3,136,44.
The UK Independence Party (Ukip) was buoyed by its receipts more than doubling to £160,000.
The two coalition parties also benefited from a shared bequest of £520,000.
Details emerged as the Electoral Commission released the latest figures for donations of more than £7,500.
The Lib Dems raised £801,448 from donations over the three months, down from £842,710 in the first quarter.
Labour also reduced its overdraft facilities by £2.5 million over the period and is listed as having outstanding loans of £12.79 million at the end of June.
The Tories are recorded as having £2.6 million of loans but have access to overdraft facilities of up to £10.13 million.
