If you provided ESTA with your email address when you applied for travel authorization, you will receive an expiration notice when your ESTA is about to expire. The email will advise you to go to the official ESTA Web site to reapply.
The flight distance between the nearest airports London (LCY) and Paris (ORY) is 218.10 mi (351.01 km). This corresponds to an approximate flight time of 0h 54min. The initial bearing on the course from London to Paris is 148.16Â° and the compass direction is SSE.
London is about 6 hours from NYC and about 8 hours from Chicago. The cheapest way to get to London is by plane. However July isn't a cheap month as that is the height of summer season. You will not find many discounted flights if at all. Expect to pay a premium to fly to London.