diff --git a/src/objects/jira_base.py b/src/objects/jira_base.py
index 2427452..b304d0f 100644
--- a/src/objects/jira_base.py
+++ b/src/objects/jira_base.py
@@ -246,6 +246,30 @@ def relate_issues(self, inward_issue: str, outward_issue: str) -> bool:
             LOGGER.error(ex)
             return False
 
+    @ignore_exceptions(retry=3, retry_interval=1, raise_final_exception=True, logger=LOGGER)
+    def close_issue(self, issue_id: str) -> None:
+        """
+        Closes a Jira issue by transitioning it to the "closed" state with a standard comment.
+
+        Args:
+            issue_id (str): The ID or key of the issue to close.
+        """
+        try:
+            issue = self.get_issue_by_id_or_key(issue_id)
+            self.logger.info("Closing issue %s with transition 'closed'...", issue_id)
+
+            self.connection.transition_issue(
+                issue=issue.key,
+                transition="closed",
+                comment="Closed by [firewatch|https://github.com/CSPI-QE/firewatch].",
+            )
+
+            self.logger.info("Issue %s has been successfully closed.", issue_id)
+        except JIRAError as e:
+            self.logger.error("Failed to close issue %s. Jira error: %s", issue_id, e.text)
+        except Exception as ex:
+            self.logger.error("Unexpected error while closing issue %s: %s", issue_id, ex)
+
     def project_exists(self, project_key: str) -> bool:
         """
         Used to validate that the "project_key" exists in the Jira server.
diff --git a/tests/unittests/objects/jira/test_firewatch_objects_jira_base_close_issue.py b/tests/unittests/objects/jira/test_firewatch_objects_jira_base_close_issue.py
new file mode 100644
index 0000000..c51a4b6
--- /dev/null
+++ b/tests/unittests/objects/jira/test_firewatch_objects_jira_base_close_issue.py
@@ -0,0 +1,96 @@
+import pytest
+from unittest.mock import MagicMock
+from jira.exceptions import JIRAError
+from pytest import MonkeyPatch
+from src.objects.jira_base import Jira
+
+
+@pytest.fixture
+def mock_jira(monkeypatch: MonkeyPatch):
+    """
+    Provides a Jira instance with a mocked __init__ and mocked dependencies
+    for testing instance methods in isolation.
+    """
+    # Patch Jira.__init__ to avoid file access and network connections
+    monkeypatch.setattr(Jira, "__init__", lambda self, jira_config_path=None: None)
+
+    # Create the instance and attach mock objects
+    jira = Jira()
+    jira.logger = MagicMock()
+    jira.get_issue_by_id_or_key = MagicMock()
+    jira.connection = MagicMock()
+    return jira
+
+
+def test_close_issue_success(mock_jira: Jira):
+    """
+    Tests the successful execution path of close_issue.
+    """
+    issue_id = "TEST-123"
+    mock_issue = MagicMock()
+    mock_issue.key = issue_id
+    mock_jira.get_issue_by_id_or_key.return_value = mock_issue
+
+    # Call the method
+    mock_jira.close_issue(issue_id)
+
+    # Assert
+    # 1. Verify the method calls
+    mock_jira.get_issue_by_id_or_key.assert_called_once_with(issue_id)
+    mock_jira.connection.transition_issue.assert_called_once_with(
+        issue=issue_id,
+        transition="closed",
+        comment="Closed by [firewatch|https://github.com/CSPI-QE/firewatch].",
+    )
+
+    # 2. Verify ALL expected logs were made
+    mock_jira.logger.info.assert_any_call("Closing issue %s with transition 'closed'...", issue_id)
+    mock_jira.logger.info.assert_any_call("Issue %s has been successfully closed.", issue_id)
+
+    # 3. Verify no errors were logged
+    mock_jira.logger.error.assert_not_called()
+
+
+def test_close_issue_jira_error(mock_jira: Jira):
+    """
+    Tests that a JIRAError is caught and logged correctly.
+    """
+    issue_id = "TEST-123"
+    error_text = "Transition not allowed"
+    mock_issue = MagicMock()
+    mock_issue.key = issue_id
+    mock_jira.get_issue_by_id_or_key.return_value = mock_issue
+
+    error = JIRAError(status_code=400, text=error_text)
+    mock_jira.connection.transition_issue.side_effect = error
+
+    # Call method
+    mock_jira.close_issue(issue_id)
+
+    # Assert
+    # Use assert_called_once_with for a stricter check than assert_any_call
+    mock_jira.logger.error.assert_called_once_with("Failed to close issue %s. Jira error: %s", issue_id, error_text)
+
+
+def test_close_issue_unexpected_exception(mock_jira: Jira):
+    """
+    Tests that a generic Exception is caught and logged correctly.
+    """
+    # Arrange
+    issue_id = "TEST-123"
+    mock_issue = MagicMock()
+    mock_issue.key = issue_id
+    mock_jira.get_issue_by_id_or_key.return_value = mock_issue
+
+    # The actual exception object is what gets logged
+    exception_object = Exception("Unexpected failure")
+    mock_jira.connection.transition_issue.side_effect = exception_object
+
+    # Call method
+    mock_jira.close_issue(issue_id)
+
+    # Assert
+    # Assert that the error was logged exactly once, with the exception object itself
+    mock_jira.logger.error.assert_called_once_with(
+        "Unexpected error while closing issue %s: %s", issue_id, exception_object
+    )