What is the penalty for not providing your TFN to your employer?

When an individual fails to provide their Tax File Number (TFN) to their employer, the employer is obligated to withhold additional tax from the employee's pay. This is because the TFN is essential for ensuring the correct amount of tax is deducted as it allows the Australian Taxation Office (ATO) to accurately match tax records. Without a TFN, the employer must apply the highest tax rate, effectively leading to more tax being withheld than what may actually be owed. This action protects both the employer and the government from complications associated with incorrect tax payments, ensuring compliance with tax laws.

The other options do not accurately reflect the consequences tied to not providing a TFN. While there may be fines or penalties for various tax-related offenses, the immediate and specific consequence related to not providing a TFN is the adjusted withholding on pay. Termination of employment is not a standard protocol in response to this issue, nor is it accurate to assert that there is no penalty at all.