diff --git a/litellm/model_prices_and_context_window_backup.json b/litellm/model_prices_and_context_window_backup.json
index 81e99f3712..6213d2c6e8 100644
--- a/litellm/model_prices_and_context_window_backup.json
+++ b/litellm/model_prices_and_context_window_backup.json
@@ -1239,7 +1239,7 @@
         "supports_vision": true,
         "tool_use_system_prompt_tokens": 346
     },
-    "apac.anthropic.claude-sonnet-4-6": {
+    "au.anthropic.claude-sonnet-4-6": {
         "cache_creation_input_token_cost": 4.125e-06,
         "cache_creation_input_token_cost_above_200k_tokens": 8.25e-06,
         "cache_read_input_token_cost": 3.3e-07,
diff --git a/model_prices_and_context_window.json b/model_prices_and_context_window.json
index 81e99f3712..6213d2c6e8 100644
--- a/model_prices_and_context_window.json
+++ b/model_prices_and_context_window.json
@@ -1239,7 +1239,7 @@
         "supports_vision": true,
         "tool_use_system_prompt_tokens": 346
     },
-    "apac.anthropic.claude-sonnet-4-6": {
+    "au.anthropic.claude-sonnet-4-6": {
         "cache_creation_input_token_cost": 4.125e-06,
         "cache_creation_input_token_cost_above_200k_tokens": 8.25e-06,
         "cache_read_input_token_cost": 3.3e-07,
diff --git a/tests/test_litellm/test_claude_opus_4_6_config.py b/tests/test_litellm/test_claude_opus_4_6_config.py
index 6ccba580bc..7ee2ea3395 100644
--- a/tests/test_litellm/test_claude_opus_4_6_config.py
+++ b/tests/test_litellm/test_claude_opus_4_6_config.py
@@ -8,9 +8,9 @@ import os
 import litellm
 
 
-def test_opus_4_6_australia_region_uses_au_prefix_not_apac():
+def test_claude_4_6_australia_region_uses_au_prefix_not_apac():
     """
-    Test that Australia region uses 'au.' prefix instead of incorrect 'apac.' prefix.
+    Test that Australia region Claude 4.6 models use 'au.' prefix instead of incorrect 'apac.' prefix.
 
     AWS Bedrock cross-region inference uses specific regional prefixes:
     - 'us.' for United States
@@ -18,7 +18,7 @@ def test_opus_4_6_australia_region_uses_au_prefix_not_apac():
     - 'au.' for Australia (ap-southeast-2)
     - 'apac.' for Asia-Pacific (Singapore, ap-southeast-1)
 
-    This test ensures the Claude Opus 4.6 model correctly uses 'au.' for Australia,
+    This test ensures the Claude 4.6 models correctly use 'au.' for Australia,
     and that 'apac.' is NOT incorrectly used for Australia region.
 
     Related: The 'apac.' prefix is valid for Asia-Pacific (Singapore) region models,
@@ -36,6 +36,14 @@ def test_opus_4_6_australia_region_uses_au_prefix_not_apac():
     assert "apac.anthropic.claude-opus-4-6-v1" not in model_data, \
         "Incorrect model entry exists: apac.anthropic.claude-opus-4-6-v1 should be au.anthropic.claude-opus-4-6-v1"
 
+    # Verify au.anthropic.claude-sonnet-4-6 exists (correct)
+    assert "au.anthropic.claude-sonnet-4-6" in model_data, \
+        "Missing Australia region model: au.anthropic.claude-sonnet-4-6"
+
+    # Verify apac.anthropic.claude-sonnet-4-6 does NOT exist (incorrect)
+    assert "apac.anthropic.claude-sonnet-4-6" not in model_data, \
+        "Incorrect model entry exists: apac.anthropic.claude-sonnet-4-6 should be au.anthropic.claude-sonnet-4-6"
+
     # Verify the au. model is registered in bedrock_converse_models
     assert "au.anthropic.claude-opus-4-6-v1" in litellm.bedrock_converse_models, \
         "au.anthropic.claude-opus-4-6-v1 not registered in bedrock_converse_models"
@@ -44,6 +52,14 @@ def test_opus_4_6_australia_region_uses_au_prefix_not_apac():
     assert "apac.anthropic.claude-opus-4-6-v1" not in litellm.bedrock_converse_models, \
         "apac.anthropic.claude-opus-4-6-v1 should not be in bedrock_converse_models"
 
+    # Verify the au. model is registered in bedrock_converse_models
+    assert "au.anthropic.claude-sonnet-4-6" in litellm.bedrock_converse_models, \
+        "au.anthropic.claude-sonnet-4-6 not registered in bedrock_converse_models"
+
+    # Verify apac. is NOT registered for this model
+    assert "apac.anthropic.claude-sonnet-4-6" not in litellm.bedrock_converse_models, \
+        "apac.anthropic.claude-sonnet-4-6 should not be in bedrock_converse_models"
+
 
 def test_opus_4_6_model_pricing_and_capabilities():
     json_path = os.path.join(os.path.dirname(__file__), "../../model_prices_and_context_window.json")