Tax identification codes are usually printed on insurance policies, and insurance institutions or tax authorities can find them on PICC's platform. In daily life, the tax preference identification code consists of 18 digits, which can make each policy truly unique. The tax identification code is issued by the commercial health insurance information platform according to the principle of "one person, one yard". Usually, after the policy comes out, the user will print it on the policy voucher. Expand data 1. Internationally, countries have different names for social security financing methods. Countries such as Norway are called "SocialSecurityContributions" (generally translated as social security tax, social security contribution or social security contribution), Britain is called "national insurance contribution" (generally translated as national insurance tax or national insurance contribution), and Ireland is called "paid related social security". The United States and other countries refer to social security financing as "tax" in their legislation (the United States refers to it as PayrollTax, while some countries classify the guaranteed financing income as "special tax" (Assessments means "tax collected"). It can be seen from the names of social security financing methods and financing income in the above countries that there is no unified expression of social security financing methods in the world, and different countries determine their own social security financing names according to different national conditions and understandings. 2. The scope of social security tax is usually the wages and salaries paid and obtained by employers and employees who participate in social insurance in their own countries and have employment relations, as well as the income of self-employed owners who have no employment relations. The tax liability of employers and employees is generally based on domestic employment, that is, employers and employees who are employed in the tax-collecting country, regardless of their nationality and residence, must bear the social insurance tax liability of that country. However, wages and salaries earned by local residents who are employed by employers but work abroad are generally not included in the scope of taxation except in some countries. 3. In line with the taxation scope of social security tax, its taxation targets are mainly the wages paid by the employer, the wages obtained by employees and the net income of self-employed owners. In practice, the basic content of social security tax is the same, although different countries have different models and different tax targets. First, the object of taxation does not include other income other than taxpayers' wages and salaries. That is, it does not include investment income, capital gains and other income items other than wages and salaries of employers and employees. However, as a tax base, wages and salaries include not only cash paid by employers, but also income in kind and other equivalents of wages and salaries. Second, it is usually stipulated that the maximum amount of taxable wages and salaries is not subject to social insurance tax. Third, personal allowances and deductions are generally not stipulated. Because the social insurance tax is subject to the principle of exclusive taxation, all the insurance funds raised will be returned to taxpayers.