Susan Walsh, File, Associated Press
FILE - In this March 22, 2013 file photo, the exterior of the Internal Revenue Service (IRS) building in Washington. Got a question for the IRS on your taxes? Online may end up being the only answer. The IRS may soon dramatically scale back telephone and face-to-face service as part of a future plan that would focus more on online accounts for the 150 million individual taxpayers and 11 million businesses seeking help and information, the agency’s official watchdog warned.

WASHINGTON — The official IRS watchdog is warning that the agency may soon dramatically scale back telephone and face-to-face service as part of a plan that would focus more on online accounts for taxpayers seeking help.

National Taxpayer Advocate Nina Olson says in an annual report to Congress that the IRS should be more open about its plans. She says the service cutbacks may mean that more people may have to turn to tax preparers and to software such as TurboTax to file their returns.

That would increase tax compliance costs for millions of filers.

Olson says millions of taxpayers don't go on the Internet and millions more are reluctant to share sensitive information online, as envisioned by an IRS plan for future operations.