WASHINGTON—Rising federal budget deficits are boosting the U.S. Treasury’s borrowing and could restrain a fast-growing economy as the cost of credit rises, too.

The yield of 10-year Treasury notes climbed above 3% for the first time since June, as the Treasury Department announced it would increase auctions of U.S. debt by an additional $30 billion over the next three months. That included higher sales of two-year, three-year and five-year notes and the introduction of a new short-term security with a two-month maturity....