U.S. stocks closed higher on Wednesday, with all three major indices notching record close.

The Dow Jones Industrial Average was up 39.32 points, or 0.18 percent, to 22,158.18. The S&P 500 gained 1.89 points, or 0.08 percent, to 2,498.37. The Nasdaq Composite Index added 5.91 points, or 0.09 percent, to 6,460.19.

Investors have kept a close eye on the progress of a possible tax reform.

U.S. Treasury Secretary Steven Mnuchin told media on Tuesday that the Trump administration would pass tax reform before 2018. He also said that the administration will release a more detailed tax reform plan by the end of this month.

U.S. President Donald Trump pushed the Congress on Aug. 30 to pass a comprehensive measure to overhaul the U.S. tax code. He vowed to reduce the corporate tax to 15 percent to attract more companies to do business in the United States.

Economists have long called for a lower corporate tax in the United States, which is the highest among OECD countries. The major hurdle is how to fund the cut.

House Speaker Paul Ryan, who insisted on a revenue-neutral approach on tax reform, said last week that Trump's goal of lowering the corporate tax rate to 15 percent would be difficult to achieve.

On the data front, the seasonally adjusted Producer Price Index for final demand advanced 0.2 percent in August, said the U.S. Labor Department in a report on Wednesday.

The index for final demand less foods, energy, and trade services increased 0.2 percent in August following no change in July. For the 12 months ended in August, prices for final demand less foods, energy, and trade services rose 1.9 percent, according to the report.