U.S. budget deficit grew slightly in first four months of FY 2015 - CBO

WASHINGTON (Reuters) - The Congressional Budget Office on Friday forecast a $195 billion U.S. budget deficit for the first four months of the current fiscal year, up from $183 billion in the same period last year.

The CBO said the $12 billion increase in the budget gap for the October-January period was largely driven by lower payments to the U.S. Treasury this year from government-controlled mortgage finance groups Fannie Mae and Freddie Mac .

Both total receipts and total outlays for the four-month period were up by about 8 percent over the prior year, the non-partisan budget agency said.

The CBO said it estimated a January 2015 deficit of $19 billion, nearly double the $10 billion deficit a year earlier as spending increased for the Social Security and Medicaid benefit programs for older Americans. Spending also rose for student loans, international assistance and health insurance subsidies under the Affordable Care Act, the CBO said.

The Treasury is expected to report final budget figures for January and the first four months of fiscal 2015 on Feb. 11.

Last week, the CBO forecast that the deficit for the full 2015 fiscal year ending Sept. 30 would dip to $468 billion from $483 billion in fiscal 2014 as the economy strengthens.

But CBO said deficits would start to rise again in 2017 due to the mounting costs of caring for the aging Baby Boom generation.

(Reporting By David Lawder; Editing by Sandra Maler and Doina Chiacu)