Which exam should I write to become a Commissioner Level Officer in Customs???

Recruitment of Commissioner Level Officer in Customs is through Indian Revenue Service (IRS). It has two branches:
1. IRS - Income Tax and
2. IRS - Central Excise and Customs.

To enter into a career as IRS officer / officer grade directly one has to pass the Civil Service Examination (CSE) conducted by UPSC. The minimum qualification required for applying for CSE is graduation from a recognised university. Candidates, who have attained 21 years of age but not attained 30 years of age on August 1st of the year of examination are eligible

Eligibility

Education:
You should have to passed graduate from the recognized university.

Age:
Age should be 21 to 30 years.
Age relaxation for (OBC 3 years , For SC/ST 5 years , For Ex-Servicemen 5 years , for PH 10 years).

Nationality:

You must be
a citizen of India, or
a subject of Nepal, or
a subject of Bhutan, or
a Tibetan refugee who came over to India before January 1, 1962, with the intention of permanently settling in India, or
a person of Indian origin who has migrated from Pakistan, Burma, Sri Lanka, East African countries of Kenya, Uganda, the United Republic of Tanzania, Zambia, Malawi, Zaire, Ethiopia and Vietnam with the intention of permanently settling in India.