Every code on your airline ticket: booking class, fare basis, ticket number and baggage

This article decodes all of it. The tables below are not illustrations — they are counted out of two real responses from the booking system TripWise.vn sells with.

Cabin and booking class are two different things

This is the most common confusion, and the most expensive one.

• Cabin — where you physically sit: Economy, Premium Economy, Business. Three or four of them.
• Booking class (RBD) — a single letter saying at which price point you bought inside that cabin. One economy cabin can hold more than ten booking classes.

Same seat, same flight, different letter, different rights. The booking class sets your fare, your checked baggage, whether you can change dates, what a change costs, whether anything is refundable, and how many miles you earn.

Vietnam Airlines' 16 booking classes, counted from real data

In a single search response, Vietnam Airlines returned 16 booking classes across 8 fare brands. This is the full mapping:

Booking class	Fare brand	Cabin	Checked baggage
P	Economy Super Lite	Economy	None
T, R, N, E	Economy Lite	Economy	1 piece × 23 kg
L, K	Economy Classic	Economy	1 piece × 23 kg
M, B	Economy Flex	Economy	1 piece × 23 kg
U	Premium Economy Classic	Premium Economy	1 piece × 32 kg
Z, W	Premium Economy Flex	Premium Economy	1 piece × 32 kg
I, D	Business Classic	Business	1 piece × 32 kg
C, J	Business Flex	Business	1 piece × 32 kg

Look at class P. In all the data we read, it is the only Vietnam Airlines fare with no checked baggage, and the only one flagged non-refundable. It is usually the cheapest row at the top of the list. If you are travelling with a suitcase, the real price of that ticket is the price shown plus a bag.

T, R, N and E are all Economy Lite with the same baggage — what differs is how many seats remain at each price. That is why fares move in steps: when the cheapest letter sells out, the system starts selling the next one.

Vietjet: same principle, different names

The low-cost carrier's data is simpler in structure but works identically:

Booking class	Fare brand
A, V, U, X	Economy Lite
R, T, N	Economy Classic
M, L	Economy Flex
B	Economy Plus
Z	Premium Economy Plus
J	Business Elite

One big difference shows plainly in the data: every Vietjet fare we read is marked non-refundable, and none of them includes checked baggage in the fare — baggage is bought separately. That is the low-cost model: a low headline price with everything else priced apart from it.

Note that the same letter means different things at different airlines. T at Vietnam Airlines is Economy Lite; T at Vietjet is Economy Classic. There is no industry-wide alphabet — each airline defines its own.

The fare basis: the most opaque line on the ticket

Alongside the booking class, a ticket carries a longer code such as TPXVNF, MVNF or C3AVNFS. This is the fare basis — the thing that identifies exactly which set of conditions applies to your ticket.

There is one reliable and useful rule: the first character of a fare basis is always the booking class. Checked against our own data:

Fare basis	Booking class	Fare brand
TPXVNF	T	Economy Lite
RPXVNF	R	Economy Lite
LPXVNF	L	Economy Classic
KPXVNF	K	Economy Classic
MVNF	M	Economy Flex
C3AVNFS	C	Business Flex
P4AVNFS	P	Economy Super Lite

The rest of the code is the airline's internal rule reference. We are not going to guess at what each character means, because the airline publishes no key for passengers, and most of the detailed decodings you will find online are guesswork. What you need to know is this: two tickets in the same cabin with different fare bases carry different conditions, and the conditions are what determine what a change costs you.

Ticket number and booking reference: not the same thing

	Booking reference (PNR)	Electronic ticket number
Shape	6 letters and digits — A1B2C3	13 digits — 738-2401234567
What it is	Your reservation record	The issued contract of carriage
Used for	Look-ups, online check-in	Refunds, changes, claims
Watch out	Having one does not mean you have a ticket	A ticket number means the ticket exists

This catches people out, and it causes real problems. Holding a reservation and issuing a ticket are two separate steps. You can hold a booking reference and still have the seat cancelled because payment was not completed in time. Only a 13-digit ticket number means the ticket actually exists. When your confirmation arrives, look for that line — if it is not there, your trip is not secured.

The first three digits are the issuing airline's IATA number: 738 is Vietnam Airlines, 978 is Vietjet. Those three digits tell you who issued the ticket even when you bought through an agency.

Baggage notation: "1PC × 23KG" is not 23 kg in total

Baggage is expressed two different ways, and confusing them is the most common reason travellers pay excess at the desk.

• Piece concept: 1PC × 23KG means one piece, of up to 23 kg. Two suitcases of 15 kg each is wrong — the total is only 30 kg, but you have two pieces. This concept is common on routes to the United States and on some international routes.
• Weight concept: 23KG means 23 kg in total, split across as many bags as you like within the size limits. This is usual on domestic and intra-Asian routes.

Vietnam Airlines' real data also spells out the cabin allowance: "1 piece + 1 accessory, not exceeding 10 kg" in economy, and "2 pieces × 9 kg + 2 kg" in business. The "accessory" is a handbag or laptop bag — counted separately, not added to the main piece.

The remaining codes you will meet

Code	Meaning
OK	Seat confirmed on that segment
RQ	Requested — not yet confirmed
NVB / NVA	Not valid before / not valid after. The ticket's validity window
NON-REF	Non-refundable
NON-END	Not endorsable — cannot be transferred to another airline
/E	Electronic ticket
SSR	Special service request — special meals, wheelchair, unaccompanied minor
INF / CHD / ADT	Infant under 2 / child / adult
MR, MS, MRS	A title, not part of the name

How the name is written

Names are always in CAPITALS, without accents, in the order SURNAME/GIVEN NAMES followed by the title. "NGUYEN/VAN A MR" means Mr Nguyen Van A — MR is not part of the name.

The name on the ticket must match the identity document you travel on. One wrong letter can mean being refused at the gate, and at many airlines a name correction costs close to the price of a new ticket.

Read your ticket in this order

When a confirmation arrives, check these five lines, in this order:

1. Is there a 13-digit ticket number? If not, you have a reservation, not a ticket.
2. Does the name match your document? Fixing it in the first few hours is usually far cheaper.
3. What letter is the booking class? Check it against the tables above to see what you actually bought.
4. Is there checked baggage, and is it piece or weight?
5. Does it say NON-REF? If so, the fare does not come back if you cancel.

Common questions

What is the difference between cabin and booking class?

The cabin is where you sit (economy, business). The booking class is a letter showing the price point within that cabin. Vietnam Airlines' economy cabin alone has 13 booking classes.

Does Vietnam Airlines class P include baggage?

In the data our system reads, P (Economy Super Lite) is the only fare with no checked baggage and it is flagged non-refundable. If you carry a suitcase, add the cost of a bag before comparing it with other fares.

What does the letter T mean on my ticket?

It depends on the airline. At Vietnam Airlines T is Economy Lite; at Vietjet T is Economy Classic. There is no industry-wide alphabet.

I have a booking reference — do I have a ticket?

Not necessarily. A six-character booking reference is only a reservation. The ticket exists once there is a 13-digit electronic ticket number.

Is "1PC × 23KG" 23 kg in total or per bag?

One piece, up to 23 kg. Two suitcases of 15 kg each exceed the allowance even though they total only 30 kg, because that is two pieces.

What do the first three digits of the ticket number mean?

They are the issuing airline's IATA number: 738 is Vietnam Airlines, 978 is Vietjet.

Why does the fare jump when I book later?

Because each booking class holds a limited number of seats. When the cheapest letter sells out the system moves to the next one at a higher price — it is not that the system "knows" you have been searching.

Want someone to read the ticket with you?

Call +84 37 463 9192 and TripWise.vn will check what a fare actually carries before you book it — particularly baggage and the right to change dates. For companies needing VAT invoices and credit terms, see corporate travel.

Read on

Airport and city codes · What ICAO and IATA are · Industry terms

Sources and dates

The booking-class, fare-brand, fare-basis and baggage tables are counted from two real search responses from the booking system TripWise.vn uses, recorded at publication, 15 September 2026. Airlines can change their fare-brand structure and what each carries; the conditions that apply are those on your own ticket.