The monthly U.S. budget deficit widened to $198.16 billion in March from $188.15 billion in the same month a year earlier, partly because some benefit payments normally made in April were shifted to March, the Treasury Department said on Wednesday.

The monthly U.S. budget deficit was the highest on record for the month of March, although the first few months of the fiscal year are often higher than the remainder of the year by historical standards, Treasury said. Economists surveyed by Reuters had forecast a $196 billion gap.

About $30 billion of benefit payments were accelerated to into March because April 1 fell on a Sunday.

The Treasury Department also noted two changes to its estimates for subsidized government programs - the Troubled Asset Relief Program and the housing and economic recovery act - increased by spending by $20 billion.

During the first six months of fiscal 2012, which began October 1, the cumulative deficit narrowed to $779.0 billion from $829.4 billion in the comparable first six months of fiscal 2011.

The government's spending in March this year was $369.4 billion, down from $339.0 billion in March 2011.

(This story corrects fourth paragraph to say estimates involved recovery act, not education programs. Corrects fifth paragraph to delete phrase about reduced government outlays)

(Reporting by Margaret Chadbourn; Editing by James Dalgleish)