IndiGo, owned by hospitality and travel company InterGlobe Enterprises, is aiming to get approval from India's market regulator in August, before hitting the market later in the year, one of the sources said.
The timing of the market debut will, however, depend on market conditions, the source said.
The sources declined to be named because they were not authorised to speak to the media.
IndiGo, founded in 2006, has used its low-cost model to stay profitable and become India's largest airline in a market enjoying double-digit growth in passenger numbers, but where most carriers lose money because of tough competition and high costs.
The airline, which flies a single type of narrow-body planes, now carries one in three of India's air travellers.
In October the carrier made a record order for 250 Airbus A320neo jets as it seeks to capture a bigger slice of India's fast-growing aviation market.
IndiGo has picked Citigroup, Kotak Investment Banking, Morgan Stanley and JP Morgan Chase as lead managers for the listing, as well as UBS and Barclays, two of the sources said.
The listing will include the sale of a mixture of primary and secondary shares, one of the sources said.
IndiGo did not immediately respond to a request for comment.
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