Yes, in the United States, it is legal for employees to discuss their wages and working conditions with coworkers. The National Labor Relations Act (NLRA) protects the rights of employees to engage in "concerted activities" for their mutual aid and protection, including discussing their wages, benefits, and other terms of employment. This protection extends to both union and non-union employees.
Employers cannot prohibit employees from discussing their salaries, wages, or benefits with one another, and they cannot retaliate against employees who engage in such discussions. Additionally, employers cannot require employees to keep their wages confidential.
It's important to note that labor laws can vary from country to country, so it's essential to check the specific laws and regulations in your country or region regarding discussing wages with coworkers. In many places, discussing wages is generally protected as a right for employees to advocate for fair and transparent compensation practices.