diff --git a/autotest/gcore/vsis3.py b/autotest/gcore/vsis3.py
index cacec03b5b45..f799185fce48 100755
--- a/autotest/gcore/vsis3.py
+++ b/autotest/gcore/vsis3.py
@@ -143,7 +143,7 @@ def test_vsis3_no_sign_request(aws_test_config_as_config_options_or_credentials)
     bucket = "noaa-goes16"
     obj = "ABI-L1b-RadC/2022/001/00/OR_ABI-L1b-RadC-M6C01_G16_s20220010001173_e20220010003546_c20220010003587.nc"
     vsis3_path = "/vsis3/" + bucket + "/" + obj
-    url = "https://" + bucket + ".s3.amazonaws.com/" + obj
+    url = "https://" + bucket + ".s3.us-east-1.amazonaws.com/" + obj
 
     with gdaltest.config_options(
         options, thread_local=False
diff --git a/port/cpl_aws.cpp b/port/cpl_aws.cpp
index 0f4606a5c8ad..550a2b8df1c7 100644
--- a/port/cpl_aws.cpp
+++ b/port/cpl_aws.cpp
@@ -1730,8 +1730,12 @@ VSIS3HandleHelper *VSIS3HandleHelper::BuildFromURI(const char *pszURI,
         osRegion = osDefaultRegion;
     }
 
-    const std::string osEndpoint = VSIGetPathSpecificOption(
+    std::string osEndpoint = VSIGetPathSpecificOption(
         osPathForOption.c_str(), "AWS_S3_ENDPOINT", "s3.amazonaws.com");
+    if (!osRegion.empty() && osEndpoint == "s3.amazonaws.com")
+    {
+        osEndpoint = "s3." + osRegion + ".amazonaws.com";
+    }
     const std::string osRequestPayer = VSIGetPathSpecificOption(
         osPathForOption.c_str(), "AWS_REQUEST_PAYER", "");
     std::string osBucket;