Tax professionals stand to gain tens to thousands of dollars in additional revenue by adding a financial planning component to their practice, according to a new survey.

The survey by Tiburon Strategic Advisors found that the average tax professional involved in financial planning generates about $242,000 in annual revenues. The survey found that tax professionals without financial planning services brought in an average of $180,000.

The survey, which was received from 1,210 participants through Tiburon's benchmarking Web site, found that the largest tax firms are increasing their investments in the financial planning side of their businesses. The largest firms, the survey says, devote about 41% of their time to financial planning, compared to 18% for the average tax services firm. "In short, the largest firms have grown because of financial planning revenues and are devoting even more time to further this trend," the survey states.

Although results will depend on firm size, Tiburon says its data indicates that a tax professional with $180,000 in current annual revenues stands to gain between $50,000 and $100,000 in additional revenues by offering financial planning services.