The prototype had its flight test in April 1929; however, due to its poor performance, it was not accepted for service by LOT Polish Airlines, and serial production was not pursued.

[1][2] Eight projects were submitted to the competition, including four by Państwowe Zakłady Lotnicze (T.200, T.400, T.600, and Y), one by Podlaska Wytwórnia Samolotów (PWS-20), and one by Samolot (MN-2).

[2][5] The competition concluded on 10 December 1928, with engineer Zbysław Ciołkosz's PWS-20 achieving second place, the best result among the entries.

[1][4] Despite its poor evaluation by the competition committee, construction of the Lublin R-IX prototype began in 1928 at the order of the Airborne and Antigas Defence League, funded by a 100,000 PLN grant from the Ministry of Transport.

[4] The prototype featured almost identical wing planforms and flight control surfaces to the R-VIII but introduced a new fuselage, welded from steel tubes, and a different propulsion system.

[4][5] From 16 May to 30 September 1929, the prototype was publicly displayed at the Polish General Exhibition in Poznań, alongside two other Lublin aircraft – R-X and R-XI.

[7] However, the Lublin R-IX was not adopted for use by LOT Polish Airlines due to its inferior performance compared to the Fokker F.VII and Junkers F 13 aircraft already in service, particularly its lower cruising speed and more time-intensive maintenance requirements.

[5][8] Consequently, its serial production was not pursued, and the only prototype was stored in the airship hangar in Poznań, where it was eventually scrapped after several years.

[5] The classic landing gear had a three-strut main assembly made of steel tubes, with Aerol oil-air shock absorbers.