There are low Delta/SkyTeam and United/Star Alliance fares from Chicago to Stockholm, Sweden at $431 round trip for departures in last two weeks of August and $465 to $485 for departures in September and October. These fares are available with Delta and United for August and then multiple SkyTeam partners KLM/Air France and Star Alliance partners including Swiss, Lufthansa, Air Canada with low fares in Sep-Oct in upper $400s round trip.
Delta Airlines Chicago New York JFK – Stockholm ARN
United Airlines Chicago ORD – Newark EWR – Stockholm, Sweden ARN
Loyalty Traveler – Hotel Promotions Guide
Hotel loyalty program points and miles promotions for Best Western Rewards, Club Carlson, Choice Privileges, Hilton HHonors, Hyatt Gold Passport, IHG Rewards Club, Marriott Rewards, Ritz Carlton Rewards, Starwood Preferred Guest and Wyndham Rewards.