1. will generate fines and late fees.

2. If you can't declare online, you must report to the tax service hall of the tax authorities.

3. It will affect the company's tax credit rating. If it is not declared on time, it will be deducted from the credit rating.

4 for long-term zero tax returns of enterprises, the tax authorities can be included in the key monitoring for tax assessment. If you find illegal activities such as concealing income, you need to pay taxes and pay late fees.

5 may be identified as runaway households, announced and rated as D taxpayers, and bear the corresponding consequences.

6. Enterprises with invoices may have fewer invoices and need to check them regularly.

7. The tax authorities can use the cost to verify the income of enterprises.

Supervision measures for key tax sources:

1. Tax registration management: Require taxpayers to register tax, so that the tax authorities can grasp the basic information of taxpayers;

2. Tax collection and management regulations: clarify tax laws, regulations and policies, and standardize taxpayers' declaration behavior;

3. Tax inspection: regularly or irregularly inspect key tax sources to ensure the authenticity and integrity of tax returns;

4. Information sharing mechanism: establish an information sharing mechanism between tax authorities and other government departments to improve the efficiency of tax administration;

5. Risk management system: establish a risk management system by using modern information technology to evaluate and monitor the risks of key tax sources.

To sum up, forgetting to declare key tax sources will lead to a series of negative effects, such as fines and late payment fees, failure to declare online, declining tax credit rating, being listed as a key monitoring object and being assessed for tax payment, being identified as a runaway and bearing serious consequences, limited use of invoices, and possible verification of corporate income by tax authorities.

Legal basis:

People's Republic of China (PRC) tax collection management law

Article 62

Taxpayers fail to file tax returns and submit tax information within the prescribed time limit, or withholding agents fail to submit tax withholding and collecting reports and relevant materials to the tax authorities within the prescribed time limit, and the tax authorities shall order them to make corrections within a time limit and may impose a fine of less than 2,000 yuan; If the circumstances are serious, a fine of not less than two thousand yuan but not more than ten thousand yuan may be imposed.