Bmibaby is a British low-cost airline and a subsidiary of British Midland PLC. It flies to destinations in Europe from its main bases at East Midlands, Manchester, Cardiff, and Birmingham. BmiBaby is a member of the bmi Diamond Club, however it is not a member of the Star Alliance so other Star Alliance airlines' passengers cannot earn points on bmibaby flights.

BmiBaby Ltd holds a United Kingdom Civil Aviation Authority Type A Operating Licence, and is permitted to carry passengers, cargo and mail on aircraft with 20 or more seats

The airline was established on 24 January 2002  and started operations on 22 March 2002 with a flight between East Midlands and Málaga.

In late autumn 2006, the airline announced an expansion programme at Birmingham International Airport increasing the number of Boeing 737 aircraft based at the airport from five to eight and the introduction of eight new routes. In February 2007, the airline announced further growth plans at Birmingham International airport with an additional Boeing 737 aircraft based at the airport, taking the total to nine and the number of routes served to 21, making it the airline's biggest base.

Boeing 737-300On 1 March 2007, the airline announced an initiative for business travellers with an 'only choose what you need' approach. Business travellers using the airline now had the option to choose from a range of services such as ticket flexibility, executive lounge access and on-line check in, and only pay for the services they used. The company also announced that bmi's frequent flyers could now gain Diamond Club miles, however, other Star Alliance airlines' frequent flyers cannot.

Unlike its sister airline, bmibaby are unable to add the points at the airport, this has to be done at time of booking.