The Indian Revenue Service (IRS) is an Indian government agency responsible for collecting and administering direct and indirect taxes). It is a central civil service under Group A of the executive branch of the Government of India, functioning under the Department of Revenue of the Ministry of Finance and is under the administrative direction of the Revenue Secretary and the ministerial command of the Minister of Finance). The IRS comprises two branches, Indian Revenue Service (Income Tax) and Indian Revenue Service (Custom & Indirect Taxes), controlled by two separate statutory bodies, the Central Board of Direct Taxes (CBDT) and the Central Board of Indirect Taxes and Customs (CBIC) ). The duties of the IRS (Income Tax) include providing tax assistance to taxpayers, pursuing and resolving instances of erroneous or fraudulent tax filings, and formulating and enforcing policy concerning income tax in India). The duties of the IRS (Customs & Indirect Taxes) include formulation and enforcement of policy concerning the Goods and Services Tax (GST) and Customs, providing assistance to taxpayers, pursuing and resolving instances of tax fraud, prevention of smuggling, and overall administration of matters related to Customs, Indirect taxes, and Narcotics.

There are two streams of recruitment to the Indian Revenue Service. IRS officers may enter the IRS by passing the Civil Services Examination (CSE), which is a three-stage competitive selection process consisting of a preliminary examination, the main examination, and an interview. It is administered by the Union Public Service Commission (UPSC). IRS officers recruited in this way are called direct recruits). On entering the service, IRS officers are mainly trained at the National Academy of Direct Taxes (NADT) at Nagpur. There is a Foundation Course for four months post which the officers receive extensive training for sixteen months in specially designed modules on taxation and allied laws, accounting, public finances, fiscal policy, office procedures, and so on. During the training, they are also sent to various field offices and organizations across India. They are also sent abroad to give global exposure to the best taxation practices worldwide.