The nation's top tax authorities issued a guideline on Tuesday for evaluating domestic and foreign companies' tax performance in light of incentives.

It's the latest step toward a transparent credit reporting system.

The new guideline is part of an effort to build a credit reporting system in which all companies and individuals are enrolled in a national credit information database by the end of 2020, according to Wang Lujin, spokesman for the State Administration of Taxation.

Under the rating system introduced by the administration, companies with the highest credit ratings are able to enjoy up to 41 incentives in 18 fields that cover financing, investment and streamlined approvals and environmental reviews on construction projects. Credit assessments will be updated annually, under the guideline.

Xu Kunlin, deputy secretary-general of the National Development and Reform Commission, said the guideline encourages companies to pay taxes as required by law and to close loopholes that foster tax evasion.

While ratings-from A to D－have been given yearly since 2003, the guideline is the latest and most comprehensive in laying out specific criteria, Xu said.

Han Guorong, deputy head of the Taxpayer Service Department of the administration, said that banks will be able to better evaluate enterprises' credit performance in the future after the administration submits credit information to the China Banking Regulatory Commission, the nation's top banking regulator.

"That can be particularly helpful for small and medium enterprises with good credit, though they may find it hard to get financing or benefits compared with large-scale State-owned enterprises amid economic downward pressure," said Han.