in principle, all invoices should be issued. According to the Measures for the Administration of Invoices of the People's Republic of China, all invoices should be issued.

however, as a matter of fact, individuals don't need invoices, and it's not a big problem if you don't open them. But the income has to be put on the account.

Measures of the People's Republic of China on the Administration of Invoices

Chapter IV Issuance and Custody of Invoices

Article 2 Units and individuals that sell goods, provide services and engage in other business activities shall collect money from foreign businesses, and the payee shall issue invoices to the payer; Under special circumstances, the payer will issue an invoice to the payee.

article 21 all units and individuals engaged in production and business activities shall obtain invoices from the payee when purchasing goods, receiving services and paying for other business activities. When obtaining an invoice, it is not allowed to change the name and amount.