Clarification on CTC and ESI Act
The term "CTC" is not used in the ESI Act, 1948, or the rules and regulations framed under it. I believe it is also not used in any labor laws. CTC reflects the cost to the company and is not considered "wages."
You can check your pay slip to determine what your "wages" are as fixed by your employer. To understand which components are considered wages, refer to definitions in various labor laws, including the Payment of Wages Act, Minimum Wages Act, and ESI Act, 1948. If the employer is adding the 4.75% employer's share of contribution to your so-called "CTC," then there is nothing wrong. However, the employer cannot deduct their share of contribution from the "wages" as defined in various enactments.