SAS operated 4 different A300 aircrafts between 1980 and 1984.
Three of them were transfered to Scanair between 1983(4)-1987 until they were sold to Conair.

SAS flew 4 different Airbus A300 between 1980 and 1984.

Registrations are:
LN-RCA (ex F-WZEN)
OY-KAA
SE-DFK, SE-DFL

SAS have registered 65 different aircrafts of the Airbus A320 family, starting from 2001.
[A319 (4), A320 (53), A321 (8)]

Most of them are still flying today, or at least flew before the pandemic started.

SAS still flies 4 different Airbus A319 since 2006.

Registrations are:
OY-KBO (D-AVKX), OY-KBP, OY-KBR, OY-KBT

SAS flew (still flies) 53 different Airbus A320 since 2012.

Registrations were/are
A320-200:
OY-KAL, OY-KAM, OY-KAN (OE-IBM), OY-KAO, OY-KAP, OY-KAR, OY-KAS, OY-KAT, OY-KAU, OY-KAW, OY-KAY
SE-RJE, SE-RJF
A320neo:
EI-SID, EI-SIE, EI-SIF, EI-SIG, EI-SIH, EI-SII
LN-RGL, LN-RGM, LG-RGN, LN-RGO
SE-DOX, SE-DOY, SE-DOZ, SE-DYC, SE-DYM, SE-ROA, SE-ROB, SE-ROC, SE-ROD, SE-ROE, SE-ROF, SE-ROG, SE-ROH, SE-ROI, SE-ROJ, SE-ROK, SE-ROL, SE-ROM, SE-RON, SE-ROO, SE-ROP, SE-ROR, SE-ROS, SE-ROT, SE-ROU, SE-ROX, SE-ROY, SE-ROZ, SE-RUA, SE-RUB

SAS still flies 8 different Airbus A321 since 2001.

Registrations are:
OY-KBB, OY-KBE, OY-KBF, OY-KBH, OY-KBK (SE-REI), OY-KBL
LN-RKI, LN-RKK (SE-REG)

SAS have registered 9 different aircrafts of the Airbus A330, starting from 2002.

Most of them are still flying today, or at least flew before the pandemic started.

SAS still has 9 different Airbus A330 registered (the first already 2002).

Registrations are:
LN-RKH, LN-RKM (OY-KBN/F-WWKK), LN-RKN (SE-REF), LN-RKO (SE-REE), LN-RKR, LN-RKS, LN-RKT, LN-RKU
SE-REH

SAS have registered 9 different aircrafts of the Airbus A340, starting from 2002.

Most of them are still flying today, or at least flew before the pandemic started.

SAS flew 8 different Airbus A340. 3 are still in use, or parked now during the Covid pandemic.

Registrations are/were:
OY-KBA, OY-KBC, OY-KBD, OY-KBI, OY-KBM
SE-REA (LN-RKF), SE-REB (LN-RKG), LN-RKP

SAS leased 1 BAC One-Eleven aircraft between August 6, 1967 and March 20, 1968
from British Eagle International. The reason for the lease was that SAS was lackaing capacity, and the lease could temporarily fill a gap while SAS was waiting for the first DC-9s.

It was primarily used on the route Copenhagen-Zurich.

SAS operated 70 different B737 aircrafts between 1993 and today.
[B737-500: 11, B737-600: 30, B737-700: 6, B737-800: 23]
With this large number of aircrafts I only show the registrations which I can match with a postcard.

Additional postcards for the various aircrafts can be found on the SAS Postcard Publisher page.

SAS flew 11 different B737-500 between 1993 and 1995.
All aircrafts but one were previously flown by Linjeflyg. At the merge Jan 1 1993 these planes and future orders were taken over by SAS.

Registrations used were:
SE-DNA, SE-DNB, SE-DNC, SE-DND, SE-DNE, SE-DNF, SE-DNG, SE-DNH, SE-DNI, SE-DNK, SE-DNL

SAS flew 30 different B737-600 between 1998 and 2019 (at least).

Registrations used were:
LN-RPA, LN-RPB, LN-RPE, LN-RPF, LN-RPG, LN-RPH
OY-KKA (LN-RPW), OY-KKB (LN-RPZ), OY-KKC (LN-RPS), OY-KKD (LN-RPT), OY-KKE, OY-KKF (LN-RCT), OY-KKG, OY-KKH, OY-KKP (LN-RPU)
SE-DNM (LN-RRO), SE-DNN (LN-RPX), SE-DNO (LN-RPY), SE-DNP (LN-RRZ), SE-DNR (LN-RRX), SE-DNS (LN-RRY), SE-DNT, SE-DNU, SE-DNX,
SE-DNY (LN-RCW), SE-DNZ (LN-RCU), SE-DTF, SE-DTH, SE-DTU, SE-DTZ (LN-RPC/OY-KKS)

SAS flew 6 different B737-700 between 1999 and 20xx (at least).

Registrations used were:
LN-RPK, LN-RPJ
OY-KKI, OY-KKR
SE-DTI, SE-DTG

SAS flew 23 different B737-700 between 2000 and 20xx (at least).

Registrations used were:
LN-RPL, LN-RPM, LN-RPN, LN-RRS, LN-RRT, LN-RRU,
SE-DTK (LN-RCN), SE-DTL (LN-RCO), SE-DTM (LN-RCP/OY-KKU), SE-DTN (LN-RPO), SE-DTO (LN-RPP), SE-DTP (LN/RPR/OY-KKT),
SE-DTR, SE-DTS (LN-RCZ), SE-DTT (LN-RCY), SE-DTX (LN-RCR), SE-DTY (LN-RCS),
SE-DYA (LN-RPD), SE-DYC, SE-DYD, SE-DYG, SE-DYH (LN-RCX), SE-DYT

SAS operated 6 different B747 aircrafts between 1971 and 1987.
4 as original users, 2 were leased.

Additional postcards for the various aircrafts can be found on the SAS Postcard Publisher page.

SAS flew 6 different B747-283 between 1971 and 1987.

Registrations used were:
LN-RNA
OY-KHA (LN-AEO)
SE-DDL (LN-AET), SE-DFZ
N4501Q, N4502R

SAS operated 18 different B767 aircrafts between 1989 and 2004.
16 as original users, 2 were leased.
[B767-200ER: 2, B767-300ER: 16]

Additional postcards for the various aircrafts can be found on the SAS Postcard Publisher page.

SAS flew 2 different B767-283ER between 1990 and 1993.

Registrations used were:
LN-RCC
SE-DKP

SAS flew 14 different B767-383ER between 1990 and 1993.

Registrations used were:
OY-KDH, OY-KDI (SE-DOA/LN-RCG), OY-KDK (SE-DOB/LN-RCI), OY-KDL, OY-KDM
LN-RCB, LN-RCD
SE-DKO (LN-RCH), SE-DKU (LN-RCK), SE-DKR (LN-RCE), SE-DKS (OY-KDN), SE-DKT (OY-KDO/LN-RCF), SE-DKX (LN-RCL), SE-DOC (LN-RCM)

SAS leased 2 different B767-3YOER between 1996 and 2000.

Registrations used were:
SE-DKY, SE-DKZ

SAS operated 28 different DC-8 aircrafts between 1960 and 1980.
26 as original users, 2 were bought from Eastern Air Lines.
[DC-8-33: 7, DC-8-55: 3, DC-8-62: 10, DC-8-63: 8]

Additional postcards for the various aircrafts can be found on the SAS Postcard Publisher page.

More postcards of Douglas-DC8 regardless of airline are found here!

SAS flew 7 different DC-8-33 between 1960 and 1971.

Registrations used were:
OY-KTA, OY-KTB
LN-MOA, LN-MOT
SE-DBA, SE-DBB, SE-DBC

SAS flew 3 different DC-8-55 between 1965 and 1975.

Registrations used were:
OY-KTC
LN-MOH
SE-DBD

SAS flew 10 different DC-8-62 between 1967 and 1987.

Registrations used were:
OY-KTD (SE-DDU), OY-KTE
LN-MOO, LN-MOG, LN-MOW, LN-MOC
SE-DBE, SE-DBF, SE-DBG, SE-DBI

SAS flew 8 different DC-8-63 between 1968 and 1988.

Registrations used were:
OY-KTF, OY-KTG, OY-KTH (LN-MOF)
LN-MOU, LN-MOY
SE-DBH, SE-DBK, SE-DBL

SAS operated 79 different DC-9 aircrafts between 1969 and 2001.
[DC-9-21: 10, DC-9-32: 5, DC-9-33F: 2, DC-9-41: 49, DC-9-51: 4, DC-9-81: 9]
With this large number of aircrafts I only show the registrations which I can match with a postcard.

Additional postcards for the various aircrafts can be found on the SAS Postcard Publisher page.

SAS flew 10 different DC-9-21 between 1968 and 2001.

Registrations used were:
OY-KGD, OY-KGE, OY-KGF
LN-RLL (OY-KIA), LN-RLM, LN-RLO
SE-DBO, SE-DBP, SE-DBR, SE-DBS

SAS flew 5 different DC-9-32 between 1967 and 1968.
All five aircrafts were leased from Swissair and was for SAS a gap filler while waiting for the DC-9-41.

Registrations used were:
OY-KGU, OY-KGW
LN-RLS
SE-DBY, SE-DBZ

SAS flew 2 different DC-9-33F between 1969 and 1988.
These aircrafts were strictly cargo planes used primarily on the European cargo network.

Registrations used were:
LN-RLW
SE-DBN

SAS flew 49 different DC-9-41 between 1968 and 2001.

Registrations used were:
OY-KGA, OY-KGB, OY-KGC, OY-KGG, OY-KGH, OY-KGI, OY-KGK, OY-KGL, OY-KGM, OY-KGN, OY-KGO, OY-KGP, OY-KGR, OY-KGS
LN-RLA, LN-RLB, LN-RLC, LN-RLD, LN-RLH, LN-RLJ, LN-RLK, LN-RLN, LN-RLP, LN-RLS, LN-RLT, LN-RLU, LN-RLX, LN-RLZ
SE-DAK, SE-DAL, SE-DAM, SE-DAN, SE-DAO, SE-DAP, SE-DAR, SE-DAS, SE-DAT, SE-DAU, SE-DAW, SE-DAX,
SE-DBM, SE-DBT, SE-DBU, SE-DBW, SE-DBX, SE-DDP, SE-DDR, SE-DDS, SE-DDT

SAS flew 3 different DC-9-51 between 1987 and 1988.
All three aircrafts were leased from Swissair primarily due lack of capacity.

In additon, also due to lack of capacity, a DC9-51 from Inex Adria was leased from Sep 26 1983 to May 31 1984.
According to some internet sources it was also leased from Oct 1984 to May 1985.
This aircraft was painted in SAS livery but was flown as YU-AJU and was never given a VIKING name.

Registrations used were:
LN-RMC (OY-CTA),
SE-DFN, SE-DFO
YU-AJU

SAS operated 12 different DC-10 aircrafts between 1974 and 1990.
All but one as original user, 1 bought from Trans Union Aircraft Leasing.
[DC-10-30: 12]

Additional postcards for the various aircrafts can be found on the SAS Postcard Publisher page.

SAS flew 12 different DC-10-30 between 1974 and 1988.

Registrations used were:
LN-RKA, LN-RKB, LN-RKC, LN-RKD
OY-KDA, OY-KDB, OY-KDC
SE-DFD, SE-DFE, SE-DFF, SE-DFG, SE-DFH

SAS operated 50 different Fokker aircrafts between 1984 and 20xx.
[Fokker F27 Friendship: 9, Fokker 50: 22, Fokker F28 Fellowship: 19]
For Fokker 50 and for F28 Fellowship I only show the registrations which I can match with a postcard.

Additional postcards for the various aircrafts can be found on the SAS Postcard Publisher page.

SAS flew 9 different Fokker F27 Friendship between 1984 and 1990.

Registrations used were:
LN-RLX, LN-RNY, LN-RNZ
OY-KAC, OY-KAD
SE-IRF, SE-IRG, SE-ITH, SE-ITI

SAS operated 19 different Fokker F28 Fellowship aircrafts between 1993 and 1999.
All aircrafts were transfered from Linjeflyg January 1st 1993 as SAS bought Linjeflyg.
For Fokker F28 Fellowship I only show the registrations which I can match with a postcard.

Additional postcards for the various aircrafts can be found on the SAS Postcard Publisher page.

SAS flew 19 different Fokker F28 Fellowship between 1993 and 1999.
All aircraft had been flown by Linjeflyg. When Linjeflyg was merged with SAS, the aircarfts were registered on SAS.

Registrations used were:

SE-DGA, SE-DGB, SE-DGC, SE-DGE, SE-DGF, SE-DGG, SE-DGH, SE-DGI, SE-DGK, SE-DGL,
SE-DGM, SE-DGN, SE-DGO, SE-DGP, SE-DGR, SE-DGS, SE-DGT, SE-DGU, SE-DGX,

SAS operated 22 different Fokker 50 aircrafts between 1989 and 2001.
For Fokker 50 I only show the registrations which I can match with a postcard.

Additional postcards for the various aircrafts can be found on the SAS Postcard Publisher page.

SAS flew 22 different Fokker 50 between 1989 and 2001.

Registrations used were:
LN-RNB, LN-RNC, LN-RND, LN-RNE, LN-RNF, LN-RNG, LN-RNH
OY-KAE, OY-KAF, OY-KAG, OY-KAH, OY-KAI, OY-KAK
SE-LFA, SE-LFB, SE-LFC, SE-LFK, SE-LFN, SE-LFO, SE-LFP, SE-LFR, SE-LFS

SAS operated a lot of different MD80 aircrafts. I will not list all possible registrations. Instead I will show the postcards I have got in my collection.

The MD-80 family consists of MD-81 (DC-9-81), MD-82, MD-83, MD-87 and MD-88.

Registrations in my collection:
OY-KGT (N19B)

Registrations in my collection:
LN-RMD, LN-RMS

Registrations in my collection:
SE-DIP

SAS operated 5 different Vickers Viking aircrafts between 1947 and 1949.
Registrations used were:

OY-DLA, OY-DLE, OY-DLI, OY-DLO, OY-DLU

Two of the aircrafts (OY-DLI and OY-DLU) crashed (1947 resp. 1949) in Öresund during approach to Copenhagen-Katrup.
The other three were sold to Misrair (Egypt) in 1949.

I have one postcard in the collection of the registrations listed above.