Reading Your Flight Itinerary Like a Frequent Traveler

Marcus Reiner · January 8, 2026 · 8 min read

Here is a small experiment worth running. Open the last flight confirmation you received and try to answer four questions without opening anything else. Which terminal do you depart from. Who physically operates each flight. What day do you arrive. How long is your connection, precisely. Most people can answer one, maybe two.

Every one of those answers is already in the document. This is a field by field tour of a typical itinerary, using a real shaped example: Boston to Athens via Frankfurt, issued on a Lufthansa ticket.

The header block

At the top you will find the booking reference and, if the ticket has been issued, the ticket number. You will also find the passenger name in airline format, surname first, no punctuation. BAKER/JAMES ANDREW MR. If your passport reads James Andrew Baker, that matches. If it reads Jaimes, you have a problem to solve today rather than at the counter.

The segment lines

Each flight appears as a segment. A typical line reads: LH 423 BOS FRA 18:35 08:05+1 Terminal E / Terminal 1 Operated by Lufthansa, Airbus A340-600, class V.

• LH 423 is the marketing flight number. LH is Lufthansa's IATA code.
• BOS and FRA are IATA airport codes, Boston Logan and Frankfurt Main.
• 18:35 is local departure time, 08:05+1 is local arrival the next calendar day.
• Terminal E is your Boston departure terminal, Terminal 1 is arrival at Frankfurt.
• Class V is your booking class, which drives your fare rules.

Operated by: the line that changes your day

If a segment says Lufthansa 9412 operated by Air Dolomiti, you are flying Air Dolomiti. Their aircraft, their crew, their carry on enforcement, their check in desk. Air Dolomiti's regional jets have smaller overhead bins than an A320, and gate checking is routine even when your Lufthansa allowance says otherwise.

The same holds for the big alliances. An American Airlines number operated by British Airways departs from British Airways check in at Heathrow Terminal 5, not from the American desks. Turning up at the wrong terminal at Heathrow costs about 25 minutes on the transit train, and that is on a good day.

Connection times, measured properly

Subtract scheduled arrival from scheduled departure and you have the connection on paper. What matters is the connection in practice, which depends on three things the itinerary hints at: whether the terminals differ, whether you cross an immigration border, and whether the airport is one where transfers are slow.

If your itinerary shows a 55 minute connection at Heathrow between Terminal 3 and Terminal 5, the system sold it because it meets the published minimum. Published minimums assume an on time arrival, a jet bridge rather than a bus, and no queue. You will want a plan B in your pocket.

Ticket status and fare details at the bottom

Scroll past the flights and you will usually find a fare summary. Look for three things:

1. The fare basis code for each segment, which tells you the conditions.
2. The endorsement box, which may say NON-REF or NON-END. NON-END means the ticket cannot be transferred to another airline during a disruption, which limits your rebooking options considerably.
3. The baggage allowance line, expressed as 1PC, 2PC or a weight such as 23K. If it says 0PC or NIL, you have no checked bag included.

Nine out of ten baggage disputes we see at the desk started as a line in the confirmation email that the passenger never opened.

Handling supervisor, Copenhagen Airport

A five minute itinerary audit

1. 01

   Match the name to the passport

   Character by character on the surname and first name. Ignore the middle name unless it is wrong.

2. 02

   Note every arrival day marker

   Write the real arrival date next to any segment with a plus or minus.

3. 03

   Check the operating carrier for each leg

   Then look up that carrier's baggage and carry on rules, not the one whose name is on your ticket.

4. 04

   Find your terminals

   Departure and arrival. At Heathrow, Paris Charles de Gaulle, New York JFK and Tokyo Narita this determines your morning.

5. 05

   Confirm the baggage line

   1PC 23K is a bag. 0PC is not. Buy it now if you need it, airport prices are roughly double.

6. 06

   Look for a ticket number

   Thirteen digits. No number, no ticket, contact the seller today.