- The FIRS is responsible for assessment of persons, companies and enterprises chargeable with Tax. They must enforce payment of this taxes as may be due to the government.
- They also in collaboration with the relevant ministries and agencies review tax regimes and promote the application of tax revenues to stimulate economic activities and development
- Adopt measures to identify, trace, freeze, confisticate or seize proceeds derived from tax fraud or evasion
- Maintain database, statistics, records and reports on persons organizations, proceeds ,properties, documents or other items or assets relating to tax administration matters and waivers, fraud or evasion
- Issue taxpayer identification number to every taxable person in Nigeria in collaboration with states boards of internal revenue and local government councils