According to ISO 15156 / NACE MR0175 standard S31803 duplex stainless steel can be used up to 0.1 b H2S and 232°C/450°F regardless of the chloride concentration and the pH. These limits are based on past studies and are very conservative.The objective of this paper is to share some recent laboratory data dealing with Sulphide Stress Cracking (SSC) and Stress Corrosion Cracking (SCC) resistance of S31803 above these limits. Corrosion resistance of the duplex material was assessed in environments representative of formation waters containing up to 120 g/l chlorides at pH=4.5. Various H2S partial pressures were considered (0.5 to 1 b) as well as different testing temperatures (25°C/77°F 90°C/194°F and 150°C/392°F). Constant load and four-point-bend tests were performed using specimens coming from three industrial heats.Results revealed the strong influence of chloride concentration and temperature on S31803 corrosion resistance. It was also demonstrated that S31803 is resistant to SSC/SCC phenomena up to 0.5 b H2S which is significantly above ISO 15156 / NACE MR0175 requirements.Key words: Duplex stainless steel chloride temperature sulphide stress cracking stress corrosion cracking sour service