Air carrier first officer reported an air return due to fumes in the aircraft.

Attributes
ACN	1717205
Time
Date	202001
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Person 1
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural Published Material / Policy Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

Narrative:

Climbing out of ZZZ the captain and I noticed a fume smell that did not dissipate. The captain called the flight attendants and they also reported the smell and that they had headaches; irritated eyes and throats. Several passengers also noticed the fumes; which appeared to be stronger in the cabin. We ran the appropriate checklist and got ATC clearance to return to ZZZ. We made an overweight but uneventful landing on runway xxr. Crash fire rescue equipment (crash fire rescue) and EMS met the aircraft and the affected passengers and cabin crew were offered appropriate care. Neither captain or first officer (first officer) had any symptoms and at no time was any smoke or fire observed by anyone.the cause of the fumes remains undetermined.

Original NASA ASRS Text

Title: Air carrier First Officer reported an air return due to fumes in the aircraft.

Narrative: Climbing out of ZZZ the Captain and I noticed a fume smell that did not dissipate. The Captain called the Flight Attendants and they also reported the smell and that they had headaches; irritated eyes and throats. Several passengers also noticed the fumes; which appeared to be stronger in the cabin. We ran the appropriate checklist and got ATC clearance to return to ZZZ. We made an overweight but uneventful landing on Runway XXR. CFR (Crash Fire Rescue) and EMS met the aircraft and the affected passengers and cabin crew were offered appropriate care. Neither Captain or FO (First Officer) had any symptoms and at no time was any smoke or fire observed by anyone.The cause of the fumes remains undetermined.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.