Chinese firms have started to accumulate better tax records, an official said Wednesday.

The State Administration of Taxation (SAT) has established a credit rating system for corporate tax payers, in which companies are ranked from A to D in terms of their tax-paying record.

Fu Shulin, deputy head of the general office of the SAT, said at a press conference that 23.9 million businesses were covered in the system at the end of June 2018, up significantly from 8.82 million in 2017.

"According to credit rating results for the past four years, the number of companies with sound credit records has been increasing, and those with poor records dropping," Fu said. "Tax-paying in general improved nationwide."

Companies ranked C or D only accounted for slightly more than 10 percent of the total, SAT data showed.

Businesses with sound tax records enjoy favorable policies. Chinese banks granted 727,000 loans to good corporate tax payers from 2015 to the first quarter of this year, with more than 80 percent to small firms, which usually struggle to obtain loans.