Scandinavian Airlines has round-trip flights from Chicago (ORD) to Stockholm, Manchester, Helsinki, Copenhagen, or Gothenburg (ARN, MAN, HEL, CPH, GOT) for $414-$448. Most flights are in April, except Copenhagen which has a range of December to April. Very few extended weekends available.
Stockholm and Copenhagen flights are NONSTOP. Other destinations have a connection.
Some small OTAs on Skyscanner and Google have this for about $394-$428; which is cheaper than the airline. If you plan on booking there, beware of any site that charges a fee to cancel a ticket within the 24-hour “free” period. Use unknown booking sites at your own risk.
Carry on bag with a maximum weight of 18 lbs is allowed for free on SAS. You can avoid seat selection fees by accepting the randomly assigned seat at the gate. Upgrading to a higher fare class that includes a full-size carry-on bag for about $35 may be cheaper than booking the discount fare with the added carry-on bag fee (for about $70).
Click for more details and booking links Cheap Flights: Chicago to Stockholm, Manchester, Helsinki, Copenhagen, or Gothenburg $394-$448 r/t [Apr / Dec-Apr] – Scandinavian Airlines