diff --git a/doc/changes/unreleased.md b/doc/changes/unreleased.md
index 93dc2f4fb..5395286c7 100644
--- a/doc/changes/unreleased.md
+++ b/doc/changes/unreleased.md
@@ -3,6 +3,7 @@
 ## Bugfixes
 
 * #397: Fixed handling empty coverage
+* #403: Removed unneeded `poetry run` from internal code of nox tasks
 
 ## Refactorings
 
diff --git a/exasol/toolbox/nox/_dependencies.py b/exasol/toolbox/nox/_dependencies.py
index 7fb01b916..a0af5ff40 100644
--- a/exasol/toolbox/nox/_dependencies.py
+++ b/exasol/toolbox/nox/_dependencies.py
@@ -263,7 +263,7 @@ def _parse_args(session) -> argparse.Namespace:
     def run(self, session: Session) -> None:
         args = self._parse_args(session)
 
-        command = ["poetry", "run", "pip-audit", "-f", "json"]
+        command = ["pip-audit", "-f", "json"]
         output = subprocess.run(command, capture_output=True)
 
         audit_json = self._filter_json_for_vulnerabilities(output.stdout)
diff --git a/exasol/toolbox/nox/_format.py b/exasol/toolbox/nox/_format.py
index a8d8efbe3..39304bdf9 100644
--- a/exasol/toolbox/nox/_format.py
+++ b/exasol/toolbox/nox/_format.py
@@ -17,8 +17,8 @@ def _code_format(session: Session, mode: Mode, files: Iterable[str]) -> None:
     def command(*args: str) -> Iterable[str]:
         return args if mode == Mode.Fix else list(args) + ["--check"]
 
-    session.run(*command("poetry", "run", "isort"), *files)
-    session.run(*command("poetry", "run", "black"), *files)
+    session.run(*command("isort"), *files)
+    session.run(*command("black"), *files)
 
 
 def _pyupgrade(session: Session, files: Iterable[str]) -> None:
diff --git a/exasol/toolbox/nox/_lint.py b/exasol/toolbox/nox/_lint.py
index 54d918ca6..82004749d 100644
--- a/exasol/toolbox/nox/_lint.py
+++ b/exasol/toolbox/nox/_lint.py
@@ -75,7 +75,7 @@ def _security_lint(session: Session, files: Iterable[str]) -> None:
 
 
 def _import_lint(session: Session, path: Path) -> None:
-    session.run("poetry", "run", "lint-imports", "--config", path)
+    session.run("lint-imports", "--config", path)
 
 
 class Dependencies:
diff --git a/exasol/toolbox/nox/_shared.py b/exasol/toolbox/nox/_shared.py
index 4b0722a45..450ae6edf 100644
--- a/exasol/toolbox/nox/_shared.py
+++ b/exasol/toolbox/nox/_shared.py
@@ -47,7 +47,7 @@ def _deny_filter(files: Iterable[Path], deny_list: Iterable[str]) -> Iterable[Pa
 
 
 def _version(session: Session, mode: Mode, version_file: Path) -> None:
-    command = ["poetry", "run", "version-check"]
+    command = ["version-check"]
     command = command if mode == Mode.Check else command + ["--fix"]
     session.run(*command, f"{version_file}")
 
diff --git a/exasol/toolbox/nox/_test.py b/exasol/toolbox/nox/_test.py
index 65ad35256..d954fd4c0 100644
--- a/exasol/toolbox/nox/_test.py
+++ b/exasol/toolbox/nox/_test.py
@@ -21,14 +21,13 @@
 def _test_command(
     path: Path, config: Config, context: MutableMapping[str, Any]
 ) -> Iterable[str]:
-    base_command = ["poetry", "run"]
     coverage_command = (
         ["coverage", "run", "-a", f"--rcfile={config.root / 'pyproject.toml'}", "-m"]
         if context["coverage"]
         else []
     )
     pytest_command = ["pytest", "-v", f"{path}"]
-    return base_command + coverage_command + pytest_command + context["fwd-args"]
+    return coverage_command + pytest_command + context["fwd-args"]
 
 
 def _unit_tests(
@@ -67,7 +66,7 @@ def _pass(
 def _coverage(
     session: Session, config: Config, context: MutableMapping[str, Any]
 ) -> None:
-    command = ["poetry", "run", "coverage", "report", "-m"]
+    command = ["coverage", "report", "-m"]
     coverage_file = config.root / ".coverage"
     coverage_file.unlink(missing_ok=True)
     _unit_tests(session, config, context)