A new report ahead of a US Senate hearing into The Domestic Partnership Benefits and Obligations Act has costed the introduction of benefits for the same-sex partners of federal employees.

More than 30,000 employees with same-sex partners would benefit if Congress enacts this bill, the Williams Institute at the UCLA School of Law reported.

Over ten years the report predicts the budgetary cost will be $675 million.

The President’s budget for 2008 totals $2.9 trillion.

Today the Senate Committee on Homeland Security and Government Affairs will hold a hearing on The Domestic Partnership Benefits and Obligations Act.

The bill would provide benefits for same-sex domestic partners of federal civilian employees on the same basis as spousal benefits and would include participation in retirement, life and health insurance programmes, and family and medical leave.

“This legislation would allow the federal government to keep pace with other top employers,” said Human Rights Campaign president Joe Solmonese.

“It is not only a matter of equal pay for equal work, but also the best way to insure that the government has access to the top talent on the same basis as the nation’s leading corporations,” he added.

“Adding partners to health care coverage is the most expensive part of the bill,” said study co-author Naomi Goldberg, the Peter J. Cooper Public Policy Fellow at the Williams Institute.

“But the cost increase of $43.5 million in year one is only 0.4% of total health care expenditures, a tiny fraction that is consistent with the experience of the thousands of private employers offering domestic partner benefits.”

Christopher Ramos, a researcher who also worked on the study, pointed out that several states and more than half of the Fortune 500 offers health insurance to domestic partners of employees.

“The federal government will find it harder to attract and retain talented employees if compensation does not keep up with the competition for employees,” he said.

“That means there’s a cost of not offering domestic partner benefits to the federal government, as well.”