BRASILIA, July 29 (Reuters) - Brazil's central government posted a $14.5 billion budget deficit in June, Treasury figures showed on Thursday, much smaller than a year ago thanks to rising tax revenues and lower crisis-related spending, but still more than economists had expected.

The government reported a primary budget deficit, excluding interest payments, of 73.6 billion reais ($14.5 billion) last month, compared with a 194.9 billion reais deficit last June.

That marked a 65% decline in real terms, Treasury said. But it was wider than the 63.4 billion shortfall forecast in a Reuters poll of economists.

Net revenue jumped 57% in real terms to 110.5 billion reais and spending fell 34.6% in real terms to 184 billion reais, Treasury said. Emergency pandemic-fighting spending in June plunged 85% from a year ago to 12.7 billion reais.

In the first half of this year the government ran a deficit of 53.7 billion reais, significantly smaller than the 417.3 billion reais deficit in the same period last year, Treasury said.

The accumulated primary deficit in the 12 months through June was 401 billion reais, worth 4.7% of gross domestic product, Treasury said.

In its bimonthly spending and revenue report last week, the Economy Ministry lowered its forecast for this year's primary budget deficit to 155.4 billion reais, or 1.8% of GDP, from a previous forecast of a 187.7 billion reais deficit.

($1 = 5.07 reais) (Reporting by Jamie McGeever Editing by Chris Reese and Leslie Adler)