UPDATE 1-Poland's estimated GDP growth raised to 4.8-4.9% in 2021 from 4% -PM

(Adds details on budget amendment)

WARSAW, Sept 21 (Reuters) - The Polish government will amend the budget for 2021 and has raised its forecast for economic growth to 4.8-4.9% from 4% previously, as the economy is faring better than expected, Prime Minister Mateusz Morawiecki said on Tuesday.

"You can amend the budget act when the situation is bad, but you can also do it when it is good. We have more revenues in the state budget than we planned for this year," Morawiecki said, announcing higher spending on healthcare, research, and support for the disabled.

The government now expects 2021 budget revenues at 483 billion zlotys ($122.72 billion) versus 404.5 billion expected earlier, the prime minister's office said on its website.

Expenditure is now planned at 523.4 billion zlotys ($132.98 billion) versus 486.8 billion ($123.69 billion) earlier, and the budget deficit is expected at 40.4 billion zlotys ($10.26 billion), half the 82.3 billion ($20.91 billion) estimated earlier.

($1 = 3.9358 zlotys) (Reporting by Pawel Florkiewicz and Anna Koper; Writing by Anna Wlodarczak-Semczuk, Editing by Catherine Evans and Bernadette Baum)