diff --git a/CHANGELOG.md b/CHANGELOG.md
index 742657d3ce5ab010ac3a7638abdb1c1ef1132f83..713f0baffc097a399288fcaa4bdebf41fb73819c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@ SPDX-License-Identifier: GPL-3.0-or-later
 [List of commits](https://git.ufz.de/rdm-software/saqc/-/compare/v2.4.0...develop)
 ### Added
 - added checks and unified error message for common inputs.
+- added command line `--version` option
 ### Changed
 - pin pandas to versions >= 2.0
 - parameter `fill_na` of `SaQC.flagUniLOF` and `SaQC.assignUniLOF` is now of type 
diff --git a/saqc/__main__.py b/saqc/__main__.py
index 42953137eaff95db8794bfff9c206741c40f1e11..f77ea9c180b59de201d1b89baf38697110701dcc 100644
--- a/saqc/__main__.py
+++ b/saqc/__main__.py
@@ -18,6 +18,7 @@ import pyarrow as pa
 from saqc.core import DictOfSeries
 from saqc.core.core import TRANSLATION_SCHEMES
 from saqc.parsing.reader import fromConfig
+from saqc.version import __version__
 
 logger = logging.getLogger("SaQC")
 
@@ -66,6 +67,7 @@ def writeData(writer_dict, df, fname):
 
 
 @click.command()
+@click.version_option(__version__)
 @click.option(
     "-c",
     "--config",
@@ -82,11 +84,16 @@ def writeData(writer_dict, df, fname):
     help="path to the data file",
 )
 @click.option(
-    "-o", "--outfile", type=click.Path(exists=False), help="path to the output file"
+    "-o",
+    "--outfile",
+    type=click.Path(exists=False),
+    required=False,
+    help="path to the output file",
 )
 @click.option(
     "--scheme",
-    default=None,
+    default="simple",
+    show_default=True,
     type=click.Choice(tuple(TRANSLATION_SCHEMES.keys())),
     help="the flagging scheme to use",
 )
@@ -94,6 +101,7 @@ def writeData(writer_dict, df, fname):
 @click.option(
     "--log-level",
     default="INFO",
+    show_default=True,
     type=click.Choice(["DEBUG", "INFO", "WARNING"]),
     help="set output verbosity",
 )
diff --git a/saqc/core/core.py b/saqc/core/core.py
index 08e49fa2d88688ba4a2c2ffd0c77f37c55c5e789..4e53116672f8fdd388b4f9fbdd2678658e06a299 100644
--- a/saqc/core/core.py
+++ b/saqc/core/core.py
@@ -35,8 +35,8 @@ np.seterr(invalid="ignore")
 
 
 TRANSLATION_SCHEMES = {
-    "float": FloatScheme,
     "simple": SimpleScheme,
+    "float": FloatScheme,
     "dmp": DmpScheme,
     "positional": PositionalScheme,
 }