The contributors of Flight-Report published 9 reviews on 2 airlines on the route Chicago - Chicago O'Hare (ORD) → Frankfurt - Frankfurt am Main (FRA). The airline with the best average rating is Lufthansa with 7.3/10. The average flight time is 8 hours and 2 minutes.
Airlines on this route are:
Frequent travelers recommend "United Polaris Lounge" at ORD for services and meals/catering.
The airport of Chicago (ORD) is rated as moderately efficient (security/immigration/police checks); make sure to arrive with sufficient time.