The discount fare is one of the promotions that the airline will be offering every week up to the date of its 25th birthday on 22 June.
Virgin Atlantic operates a daily flight to Chicago from London Heathrow, departing from the UK at 11:00 and arriving at O'Hare airport at 13:55 local time.
The one-off fares of £250 for economy class and £499 for premium economy are available for sale until 1 April and are valid for travel from today (26 March) to 3 April or between 8 April and 31 May.
Virgin Atlantic has been operating a promotional campaign this year claiming that it is 'still red hot' as it approaches its 25th anniversary.
The airline was recently able to launch round-the-world fares following the introduction of flights from Sydney to Los Angeles by its subsidiary V Australia.