Date: 202007
Local time of day: 0001-0600
Location: ZZZ.Airport, US
Weather elements / visibility: Rain
Aircraft: Heavy Transport
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Flight phase: Taxi; Takeoff / Launch
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness; Communication Breakdown; Confusion
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: General None Reported / Taken
Contributing factors: Weather; Environment - Non Weather Related; Human Factors
Primary problem: Human Factors

Narrative: Operating Flight ABC ZZZ to ZZZ1. Neither the Captain nor FO were very familiar with ZZZ and with steady rain; and as the FO; I was focused on providing taxi instructions to the Captain from the south ramp until cleared to cross XXC. While crossing XXC; the Tower initially cleared us to turn right on Taxiway X to YY.  After turning onto X; I commenced the before takeoff checklist which was interrupted by a Tower transmission for us to turn right onto X; which we had already done. This created momentary confusion for the crew but I completed the checklist; briefing YYR full length.  Just as I completed the before takeoff checklist; Tower cleared us onto the runway and cleared us for takeoff. A proper runway verification was not done; the expectation was for full length and as the flying pilot I did not have the situational awareness; nor did the entire crew; that the aircraft was at an intersection while accepting a clearance onto the runway for departure. We commenced a normal takeoff with the FO as the flying pilot and at V1 it appeared that we had used up more than the normal amount of runway; at rotate speed I commenced a normal rotation with roughly 2;000 feet of runway remaining.  After initial climbout; the crew discussed the fact that the takeoff roll had used up too much runway.  Upon further investigation we realized we had taken off from intersection YY/YYR with takeoff numbers for full length on Runway YYR. We had briefed full length YYR during the preflight taxi briefing and had selected full length YYR (wet runway) when requesting takeoff numbers.The crew as a whole did not perceive the threat that we could be given an intersection takeoff nor did we catch the error that we had numbers for full length while accepting an intersection departure. This error was not repaired and the crew put themselves and the aircraft into an undesirable and improper state.  Monitoring/crosschecking along with situational awareness were the major CRM skills that were lacking. As a crew we discussed this at length during the flight and the remainder of the flight proceeded normally.As a crew we could have aided in averting this situation by using our CRM skills by discussing or realizing that we may be assigned an intersection departure in ZZZ; the flying pilots were both from ZZZ2 where intersection takeoffs are not relevant. The fact that very few of us on this type aircraft are flying normal schedules in the current environment and that we may be operating under abnormal personal stress or out of airports we normally don't operate out of requires that we double our efforts to ensure we employ the very best of our CRM skills to ensure we all have the situational awareness to ensure continued safe operations.




Synopsis: Air carrier First Officer reported they had numbers for a full runway takeoff; but were given and executed an intersection takeoff.