Does anyone know of a good source for a complete listing and explanation of Delta's fare codes?

This is the best I've found. Keep in mind that a fare code will have different conditions for different city pairs.

This is really dated but probably still 90% accurate.

From Expertflyer:

A DL FIRST CLASS
AN DL FIRST CLASS
B DL COACH
BN DL ECONOMY
C DL BUSINESS CLASS
CN DL BUSINESS
D DL BUSINESS CLASS
DN DL DELUXE NIGHT
E DL Coach - Promotional Award
F DL FIRST CLASS
FN DL DELUXE NIGHT
G DL First - Domestic PMU upgrade
H DL COACH
HN DL ECONOMY
I DL BUSINESS
J DL BUSINESS
K DL COACH
KN DL ECONOMY
L DL COACH
M DL COACH
N DL Coach - Award
O DL Business Elite - Award
P DL FIRST CLASS
Q DL COACH
R DL First - Domestic Award
S DL COACH
T DL ECONOMY
U DL ECONOMY
V DL First - Domestic segment upgrade
W DL PREM ECONOMY CLASS
X DL Business - Domestic segment upgrade
Y DL COACH
YN DL ECONOMY
Z DL Business Elite - Upgrade with PMU or points

I've never heard of or seen the "xN" fare classes, nor have I ever heard of a "DL Deluxe Night" fare? What are these?

X/N/V booking classes are not for sale. These are award based inventory types for free tickets and upgrades. X is for a business elite upgrade on domestic flights, just like a V would be for first.

Several answers are providing references for fare classes rather than fare codes. Which did the OP actually mean?

I use this page as well. I think it's more accurate than 90% but I could be wrong.

http://www.cwsi.net/delta.htm

In the old days, and I think even during the regulated years, "Night Coach" fares were one of the few discounted fare classes sold. The real old timers here should remember when Delta would advertise its "Early Bird" and "Owly Bird" fares which were "xN" fare classes. These were ususally the first thing in the morning flights and the evening flights. I don't think you see them at all any more.

Fare codes with a N after them, e.g. Yn denoted night fares which were generally sold at a discount. They were usually available for flights that departed between 10:00 pm and 5:00am and are left overs from the regulated days. Yn was commonly referred to as "night coach". You would also see Fn. As discounted fare buckets were created they pretty much disappeared. I can't recall the last time I saw one.

Sorry, my typing wasn't clear. I know X and N class are award fares.

If you look carefully you will see several fares that are two characters. The first character is a normal fare letter like "A", "B", "C", "D", or "F". The second character in these fares is "N". The description is "Delta Deluxe". I've never seen these two character fares, and I've never heard of "Delta Deluxe" fares. What are they?

Several people have provided lists of fare classes. If you want a list of fare codes these are route and timeframe specific. You can find them on the likes of Travelocity by selecting the city pair, time period and listing only Delta fares.

Or here (at least some of them):


Fare Basis Booking Class

U21M3NBV DL U
L14M3NBV DL L
LLXNR5 DL L
LLWNR5 DL L
KLXNR5 DL K
KLWNR5 DL K
K14M3NBV DL K
QLXAB4 DL Q
QLWAB4 DL Q
Q7M3NBV DL Q
HLXAB3 DL H
HLWAB3 DL H
H7NBV DL H
MAP1 DL M
BPXE1 DL B
BEE DL B
ILLEISL DL I
BDK DL B
Y0BV DL Y
Y DL Y
YUPBV DL A
F0BV DL F
F DL F
DR DL D
D DL D
CR DL C
JR DL J
J DL J
C DL C

The "some of" is exactly my point! Even if one compiled a full list today, chances are it would change on Monday!

You are of course right!!.

These were sampled from Expertflyer on a SLC-ATL and ATL-CPH route in December 2006!!