Bihar has three operational airports : Lok Nayak Jayaprakash Airport, Patna, Gaya Airport, Gaya and Chunapur Airport, Purnea.

The Patna airport is categorised as a restricted international airport, with customs facilities to receive international chartered flights. The Patna airport is connected to Delhi, Mumbai, Kolkata, Lucknow, Bangaluru, Hyderabad, Chennai, Pune, Ranchi and Kathmandu.

The Gaya Airport is an international airport connected to Colombo, Singapore and Bangkok.

The Purnea Airport is small airport handling limited charted flights.

Bihar is very well-connected by railway lines to the rest of India. Most of the towns are interconnected, and they are also connected directly to Kolkata, Delhi and Mumbai (as well as most other major cities in India). Daily or weekly trains connect Patna and other major cities in Bihar to Dibrugarh, Guwahati, Siliguri in the North East, to Hyderabad, Vizag, Bangalore, Chennai, Coimbatore, Kochi and Thiruvananthapuram in the South, to Nagpur, Raipur, Bhilai, Bhopal and Indore in Central India, and to Goa, Pune, Surat, Baroda, Ahmedabad, Ajmer, Bikaner and Jaipur in Western India. There are also frequent (often multiple daily) connections to several towns in neighbouring Bengal, Orissa, Jharkhand, Uttar Pradesh and to the Northern states of Haryana and Punjab. Patna, Gaya, Bhagalpur, Muzaffarpur, Darbhanga, Katihar, Barauni, Chhapra, Siwan abd Dehri on Sone are Bihar's best-connected railway stations. Nepal Railways operates two railway lines: a 6 km broad gauge line from Raxaul in India to Sirsiya Inland Container Depot or Dry Port near Birganj in Nepal and a 53 km 762 mm (2 ft 6 in) narrow gauge line from Jaynagar in India to Bijalpura in Nepal. The latter line is composed of two sections: 32 km between Jaynagar and Janakpur and 21 km from Janakpur to Bijalpura. The Janakpur line is used largely for passengers and the Sirsiya (Birganj) line only for cargo freight.

The state has a vast network of National and State highways. East-West corridor goes through the cities of Bihar (Muzaffarpur-Darbhanga-Purnia NH57).

For Buddhist pilgrims, the best option for travel to Bihar is to reach Patna or Gaya, either by air or train, and then travel to Bodh Gaya, Nalanda, Rajgir and Vaishali. Sarnath in Uttar Pradesh is also not very far.

The Ganges – navigable throughout the year – was the principal river highway across the vast north Indo-Gangetic Plain. Vessels capable of accommodating five hundred merchants were known to ply this river in the ancient period; Goods were carried from Pataliputra (later Patna) and Champa (later Bhagalpur) out to the seas and to ports in Sri Lanka and Southeast Asia. The role of the Ganges as a channel for trade was enhanced by its natural links – it embraces all the major rivers and streams in both north and south Bihar.

In recent times, Inland Waterways Authority of India has declared the Ganges between Allahabad and Haldia to be a national inland waterway and has taken steps to restore its navigability.