diff --git a/pyproject.toml b/pyproject.toml
index 5c2527cd9b8..f50b474fdc2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -208,7 +208,6 @@ ignore = [
     "PLW0604", # global-at-module-level
     "PLW1508", # invalid-envvar-default
     "PLW1510", # subprocess-run-without-check
-    "PLW1514", # unspecified-encoding
     "PLW1641", # eq-without-hash
     "PLW2901", # redefined-loop-name
     "PLW3201", # bad-dunder-method-name
@@ -288,62 +287,163 @@ ignore = [
 "gui/**" = ["PLW0108"] # See https://github.com/OSGeo/grass/issues/4124
 # Other ignores:
 "**.py" = ["PYI066"]
-"*/testsuite/**.py" = ["PT009", "PT027"]
+"*/testsuite/**.py" = ["PT009", "PT027", "PLW1514"]
+"display/d.mon/render_cmd.py" = ["PLW1514"]
+"display/d.text/test.py" = ["PLW1514"]
+"gui/wxpython/animation/temporal_manager.py" = ["PLW1514"]
+"gui/wxpython/core/gconsole.py" = ["PLW1514"]
+"gui/wxpython/core/render.py" = ["PLW1514"]
+"gui/wxpython/core/settings.py" = ["PLW1514"]
+"gui/wxpython/core/toolboxes.py" = ["PLW1514"]
+"gui/wxpython/core/utils.py" = ["PLW1514"]
+"gui/wxpython/core/watchdog.py" = ["PLW1514"]
+"gui/wxpython/core/workspace.py" = ["PLW1514"]
+"gui/wxpython/dbmgr/base.py" = ["PLW1514"]
+"gui/wxpython/docs/wxgui_sphinx/conf.py" = ["PLW1514"]
+"gui/wxpython/gcp/manager.py" = ["PLW1514"]
+"gui/wxpython/gmodeler/model.py" = ["PLW1514"]
+"gui/wxpython/gmodeler/panels.py" = ["PLW1514"]
+"gui/wxpython/gui_core/forms.py" = ["PLW1514"]
+"gui/wxpython/gui_core/ghelp.py" = ["PLW1514"]
+"gui/wxpython/gui_core/goutput.py" = ["PLW1514"]
+"gui/wxpython/gui_core/gselect.py" = ["PLW1514"]
+"gui/wxpython/gui_core/pyedit.py" = ["PLW1514"]
+"gui/wxpython/gui_core/widgets.py" = ["PLW1514"]
+"gui/wxpython/iclass/frame.py" = ["PLW1514"]
 "gui/wxpython/iclass/statistics.py" = ["A005"]
-"gui/wxpython/wxplot/profile.py" = ["A005", "SIM115"]
+"gui/wxpython/image2target/ii2t_gis_set.py" = ["PLW1514"]
+"gui/wxpython/image2target/ii2t_manager.py" = ["PLW1514"]
+"gui/wxpython/location_wizard/wizard.py" = ["PLW1514"]
+"gui/wxpython/mapdisp/main.py" = ["PLW1514"]
+"gui/wxpython/modules/colorrules.py" = ["PLW1514"]
+"gui/wxpython/modules/mcalc_builder.py" = ["PLW1514"]
+"gui/wxpython/photo2image/ip2i_manager.py" = ["PLW1514"]
+"gui/wxpython/psmap/instructions.py" = ["PLW1514"]
+"gui/wxpython/rdigit/controller.py" = ["PLW1514"]
+"gui/wxpython/rlisetup/frame.py" = ["PLW1514"]
+"gui/wxpython/rlisetup/wizard.py" = ["PLW1514"]
+"gui/wxpython/tools/update_menudata.py" = ["PLW1514"]
+"gui/wxpython/tplot/frame.py" = ["PLW1514"]
+"gui/wxpython/vdigit/mapwindow.py" = ["PLW1514"]
+"gui/wxpython/vnet/vnet_core.py" = ["PLW1514"]
+"gui/wxpython/vnet/vnet_data.py" = ["PLW1514"]
+"gui/wxpython/web_services/dialogs.py" = ["PLW1514"]
+"gui/wxpython/wxplot/profile.py" = ["A005", "PLW1514", "SIM115"]
+"imagery/i.atcorr/create_iwave.py" = ["PLW1514"]
 "lib/imagery/testsuite/test_imagery_sigsetfile.py" = ["FURB152"]
-"lib/init/grass.py" = ["SIM115"]
+"lib/init/grass.py" = ["PLW1514", "SIM115"]
 "lib/init/testsuite/test_grass_tmp_mapset.py" = ["PTH208"]
 "locale/grass_po_stats.py" = ["SIM115"]
-"man/build.py" = ["PTH208"]
-"man/build_class_graphical.py" = ["PTH208"]
-"man/build_manual_gallery.py" = ["PTH208"]
-"man/build_rest.py" = ["PTH208"]
+"man/build.py" = ["PLW1514", "PTH208"]
+"man/build_class.py" = ["PLW1514"]
+"man/build_class_graphical.py" = ["PLW1514", "PTH208"]
+"man/build_full_index.py" = ["PLW1514"]
+"man/build_graphical_index.py" = ["PLW1514"]
+"man/build_html.py" = ["PLW1514"]
+"man/build_index.py" = ["PLW1514"]
+"man/build_index_rest.py" = ["PLW1514"]
+"man/build_keywords.py" = ["PLW1514"]
+"man/build_manual_gallery.py" = ["PLW1514", "PTH208"]
+"man/build_md.py" = ["PLW1514"]
+"man/build_rest.py" = ["PLW1514", "PTH208"]
+"man/build_topics.py" = ["PLW1514"]
+"man/parser_standard_options.py" = ["PLW1514"]
 "python/grass/__init__.py" = ["PYI056"]
 "python/grass/exp*/tests/grass_script_mapset_session_test.py" = ["SIM117"]
 "python/grass/exp*/tests/grass_script_tmp_mapset_session_test.py" = ["SIM117"]
-"python/grass/gunittest/case.py" = ["PT009"]
+"python/grass/gunittest/case.py" = ["PLW1514", "PT009"]
+"python/grass/gunittest/checkers.py" = ["PLW1514"]
+"python/grass/gunittest/invoker.py" = ["PLW1514"]
 "python/grass/gunittest/loader.py" = ["PTH208"]
+"python/grass/gunittest/reporters.py" = ["PLW1514"]
 "python/grass/gunittest/testsu*/d*/s*/s*/subsub*/t*/test_segfaut.py" = ["B018"]
 "python/grass/imaging/images2ims.py" = ["PTH208"]
 "python/grass/jupyter/testsuite/interactivemap_test.py" = ["PGH004"]
 "python/grass/jupyter/testsuite/map_test.py" = ["PGH004"]
+"python/grass/jupyter/utils.py" = ["PLW1514"]
 "python/grass/pydispatch/signal.py" = ["A005"]
-"python/grass/pygrass/gis/__init__.py" = ["PTH208"]
-"python/grass/pygrass/modules/grid/grid.py" = ["PTH208", "SIM115"]
+"python/grass/pygrass/gis/__init__.py" = ["PLW1514", "PTH208"]
+"python/grass/pygrass/modules/grid/grid.py" = ["PLW1514", "PTH208", "SIM115"]
 "python/grass/pygrass/modules/grid/testsuite/test_*_modules_grid_doctests.py" = ["F401"]
-"python/grass/pygrass/modules/interface/env.py" = ["SIM115"]
+"python/grass/pygrass/modules/interface/env.py" = ["PLW1514", "SIM115"]
 "python/grass/pygrass/modules/testsuite/test_pygrass_modules_doctests.py" = ["F401"]
-"python/grass/pygrass/raster/category.py" = ["FURB189"]
-"python/grass/pygrass/raster/segment.py" = ["SIM115"]
+"python/grass/pygrass/raster/category.py" = ["FURB189", "PLW1514"]
+"python/grass/pygrass/raster/segment.py" = ["PLW1514", "SIM115"]
 "python/grass/pygrass/tests/*.py" = ["SIM115"]
+"python/grass/pygrass/tests/set_mapset.py" = ["PLW1514"]
 "python/grass/pygrass/utils.py" = ["PTH208"]
 "python/grass/pygrass/vector/geometry.py" = ["PYI024"]
 "python/grass/pygrass/vector/testsuite/test_table.py" = ["PLW0108"]
 "python/grass/script/array.py" = ["A005"]
-"python/grass/script/core.py" = ["PTH208"]
-"python/grass/script/utils.py" = ["FURB189"]
-"python/grass/temporal/aggregation.py" = ["SIM115"]
-"python/grass/temporal/register.py" = ["SIM115"]
-"python/grass/temporal/stds_export.py" = ["SIM115"]
-"python/grass/temporal/stds_import.py" = ["SIM115"]
+"python/grass/script/core.py" = ["PLW1514", "PTH208"]
+"python/grass/script/db.py" = ["PLW1514"]
+"python/grass/script/raster.py" = ["PLW1514"]
+"python/grass/script/setup.py" = ["PLW1514"]
+"python/grass/script/utils.py" = ["FURB189", "PLW1514"]
+"python/grass/semantic_label/reader.py" = ["PLW1514"]
+"python/grass/temporal/abstract_space_time_dataset.py" = ["PLW1514"]
+"python/grass/temporal/aggregation.py" = ["PLW1514", "SIM115"]
+"python/grass/temporal/register.py" = ["PLW1514", "SIM115"]
+"python/grass/temporal/stds_export.py" = ["PLW1514", "SIM115"]
+"python/grass/temporal/stds_import.py" = ["PLW1514", "SIM115"]
 "python/grass/temporal/temporal_algebra.py" = ["D300"]
 "python/grass/temporal/temporal_operator.py" = ["D300"]
-"python/grass/temporal/univar_statistics.py" = ["SIM115"]
+"python/grass/temporal/univar_statistics.py" = ["PLW1514", "SIM115"]
 "python/grass/utils/download.py" = ["PTH208", "SIM115"]
 "raster/r.*/testsuite/*.py" = ["SIM115"]
+"raster/r.mfilter/benchmark/benchmark_r_mfilter_nprocs.py" = ["PLW1514"]
 "raster/r.topidx/*.py" = ["SIM115"]
-"scripts/d.correlate/d.correlate.py" = ["SIM115"]
-"scripts/d.frame/d.frame.py" = ["SIM115"]
-"scripts/d.polar/d.polar.py" = ["FURB154", "SIM115"]
-"scripts/db.test/db.test.py" = ["SIM115"]
+"raster/r.topidx/arc_to_gridatb.py" = ["PLW1514"]
+"raster/r.topidx/gridatb_to_arc.py" = ["PLW1514"]
+"scripts/d.correlate/d.correlate.py" = ["PLW1514", "SIM115"]
+"scripts/d.frame/d.frame.py" = ["PLW1514", "SIM115"]
+"scripts/d.out.file/d.out.file.py" = ["PLW1514"]
+"scripts/d.polar/d.polar.py" = ["FURB154", "PLW1514", "SIM115"]
+"scripts/d.to.rast/d.to.rast.py" = ["PLW1514"]
+"scripts/d.what.rast/d.what.rast.py" = ["PLW1514"]
+"scripts/d.what.vect/d.what.vect.py" = ["PLW1514"]
+"scripts/db.in.ogr/db.in.ogr.py" = ["PLW1514"]
+"scripts/db.test/db.test.py" = ["PLW1514", "SIM115"]
+"scripts/db.univar/db.univar.py" = ["PLW1514"]
 "scripts/g.download.project/g.download.project.py" = ["PTH208"]
-"scripts/g.extension.all/g.extension.all.py" = ["SIM115"]
-"scripts/g.extension/g.extension.py" = ["PTH208", "SIM115"]
+"scripts/g.extension.all/g.extension.all.py" = ["PLW1514", "SIM115"]
+"scripts/g.extension/g.extension.py" = ["PLW1514", "PTH208", "SIM115"]
+"scripts/g.search.modules/g.search.modules.py" = ["PLW1514"]
+"scripts/i.in.spotvgt/i.in.spotvgt.py" = ["PLW1514"]
+"scripts/i.oif/i.oif.py" = ["PLW1514"]
 "scripts/i.oif/i.oif*.py" = ["SIM115"]
-"scripts/m.proj/m.proj.py" = ["SIM115"]
+"scripts/i.pansharpen/i.pansharpen.py" = ["PLW1514"]
+"scripts/i.spectral/i.spectral.py" = ["PLW1514"]
+"scripts/m.proj/m.proj.py" = ["PLW1514", "SIM115"]
+"scripts/r.fillnulls/r.fillnulls.py" = ["PLW1514"]
+"scripts/r.in.srtm/r.in.srtm.py" = ["PLW1514"]
 "scripts/r.in.wms/wms_*.py" = ["SIM115"]
+"scripts/r.in.wms/wms_base.py" = ["PLW1514"]
+"scripts/r.in.wms/wms_gdal_drv.py" = ["PLW1514"]
+"scripts/r.pack/r.pack.py" = ["PLW1514"]
+"scripts/r.tileset/r.tileset.py" = ["PLW1514"]
+"scripts/r.unpack/r.unpack.py" = ["PLW1514"]
 "scripts/v.*/v.*.py" = ["SIM115"]
+"scripts/v.db.addcolumn/v.db.addcolumn.py" = ["PLW1514"]
+"scripts/v.db.addtable/v.db.addtable.py" = ["PLW1514"]
+"scripts/v.db.droptable/v.db.droptable.py" = ["PLW1514"]
+"scripts/v.db.reconnect.all/v.db.reconnect.all.py" = ["PLW1514"]
+"scripts/v.db.univar/v.db.univar.py" = ["PLW1514"]
+"scripts/v.import/v.import.py" = ["PLW1514"]
+"scripts/v.in.e00/v.in.e00.py" = ["PLW1514"]
+"scripts/v.in.lines/v.in.lines.py" = ["PLW1514"]
+"scripts/v.in.mapgen/v.in.mapgen.py" = ["PLW1514"]
+"scripts/v.in.wfs/v.in.wfs.py" = ["PLW1514"]
+"scripts/v.rast.stats/v.rast.stats.py" = ["PLW1514"]
+"scripts/v.report/v.report.py" = ["PLW1514"]
+"scripts/v.unpack/v.unpack.py" = ["PLW1514"]
+"temporal/t.list/t.list.py" = ["PLW1514"]
+"temporal/t.rast.colors/t.rast.colors.py" = ["PLW1514"]
+"temporal/t.rast.series/t.rast.series.py" = ["PLW1514"]
+"temporal/t.rast.what/t.rast.what.py" = ["PLW1514"]
+"temporal/t.remove/t.remove.py" = ["PLW1514"]
+"temporal/t.unregister/t.unregister.py" = ["PLW1514"]
+"utils/*.py" = ["PLW1514"]
 
 [tool.ruff.lint.flake8-import-conventions.extend-aliases]
 # Declare a custom aliases, checked with rule ICN001
diff --git a/python/grass/gunittest/invoker.py b/python/grass/gunittest/invoker.py
index 592d39401f8..bf94ec1185e 100644
--- a/python/grass/gunittest/invoker.py
+++ b/python/grass/gunittest/invoker.py
@@ -47,7 +47,7 @@
 # TODO: this might be more extend then update
 def update_keyval_file(filename, module, returncode):
     if os.path.exists(filename):
-        keyval = text_to_keyvalue(Path(filename).read_text(), sep="=")
+        keyval = text_to_keyvalue(Path(filename).read_text(encoding="utf-8"), sep="=")
     else:
         keyval = {}
 
@@ -66,7 +66,7 @@ def update_keyval_file(filename, module, returncode):
     keyval["returncode"] = returncode
     keyval["test_file_authors"] = test_file_authors
 
-    Path(filename).write_text(keyvalue_to_text(keyval))
+    Path(filename).write_text(keyvalue_to_text(keyval), encoding="utf-8")
     return keyval
 
 
@@ -351,7 +351,8 @@ def run_in_location(
             " (testsuite directories)</li>"
             '<li><a href="testfiles.html">Results by test files</a></li>'
             "<ul>"
-            "</body></html>".format(location=location, type=location_type)
+            "</body></html>".format(location=location, type=location_type),
+            encoding="utf-8",
         )
 
         testsuite_dir_reporter = TestsuiteDirReporter(
diff --git a/python/grass/gunittest/main.py b/python/grass/gunittest/main.py
index 14cc7e03e9b..7cd64cfa24f 100644
--- a/python/grass/gunittest/main.py
+++ b/python/grass/gunittest/main.py
@@ -64,7 +64,7 @@ def __init__(
         text_result = TextTestResult(
             stream=_WritelnDecorator(sys.stderr), descriptions=True, verbosity=verbosity
         )
-        with open("test_keyvalue_result.txt", "w") as keyval_file:
+        with open("test_keyvalue_result.txt", "w", encoding="utf-8") as keyval_file:
             keyval_result = KeyValueTestResult(stream=keyval_file)
             result = MultiTestResult(results=[text_result, keyval_result])
 
diff --git a/python/grass/gunittest/multireport.py b/python/grass/gunittest/multireport.py
index bec6a5927d2..19a5533febc 100644
--- a/python/grass/gunittest/multireport.py
+++ b/python/grass/gunittest/multireport.py
@@ -405,7 +405,7 @@ def main_page(
     directory: StrPath | None = None,
 ) -> None:
     filename = os.path.join(directory, filename)
-    with open(filename, "w") as page:
+    with open(filename, "w", encoding="utf-8") as page:
         page.write(
             "<html><body>"
             "<h1>{title}</h1>"
@@ -507,7 +507,9 @@ def main():
                 # skipping incomplete reports
                 # use only results list for further processing
                 continue
-            summary = text_to_keyvalue(Path(summary_file).read_text(), sep="=")
+            summary = text_to_keyvalue(
+                Path(summary_file).read_text(encoding="utf-8"), sep="="
+            )
             if use_timestamps:
                 test_timestamp = datetime.datetime.fromtimestamp(
                     os.path.getmtime(summary_file)
@@ -551,7 +553,9 @@ def main():
         except KeyError as e:
             print("File %s does not have right values (%s)" % (report, e.message))
 
-    with open(os.path.join(output, "index.html"), "w") as locations_main_page:
+    with open(
+        os.path.join(output, "index.html"), "w", encoding="utf-8"
+    ) as locations_main_page:
         locations_main_page.write(
             "<html><body>"
             "<h1>Test reports grouped by location type</h1>"
diff --git a/python/grass/gunittest/reporters.py b/python/grass/gunittest/reporters.py
index db6a9dcf4c2..6ea05d60d39 100644
--- a/python/grass/gunittest/reporters.py
+++ b/python/grass/gunittest/reporters.py
@@ -465,7 +465,7 @@ def wrap_stdstream_to_html(
 ) -> None:
     before = "<html><body><h1>%s</h1><pre>" % (module.name + " " + stream)
     after = "</pre></body></html>"
-    with open(outfile, "w") as html, open(infile) as text:
+    with open(outfile, "w", encoding="utf-8") as html, open(infile) as text:
         html.write(before)
         html.writelines(color_error_line(html_escape(line)) for line in text)
         html.write(after)
@@ -483,7 +483,7 @@ def html_file_preview(filename):
     html = StringIO()
     html.write(before)
     if size < max_size:
-        with open(filename) as text:
+        with open(filename, encoding="utf-8") as text:
             for line in text:
                 html.write(color_error_line(html_escape(line)))
     elif size < 10 * max_size:
@@ -568,7 +568,7 @@ def start(self, results_dir):
         # having all variables public although not really part of API
         main_page_name = os.path.join(results_dir, self._main_page_name)
         # TODO: Ensure file is closed in all situations
-        self.main_index = open(main_page_name, "w")  # noqa: SIM115
+        self.main_index = open(main_page_name, "w", encoding="utf-8")  # noqa: SIM115
 
         # TODO: this can be moved to the counter class
         self.failures = 0
@@ -794,7 +794,7 @@ def end_file_test(
             # using constructors as seems advantageous for counting
             self._file_anonymizer.anonymize(supplementary_files)
 
-        with open(file_index_path, "w") as file_index:
+        with open(file_index_path, "w", encoding="utf-8") as file_index:
             file_index.write(header)
             file_index.write(summary_section)
             if modules:
@@ -897,7 +897,7 @@ def finish(self):
 
         summary_filename = os.path.join(self.result_dir, "test_keyvalue_result.txt")
         text = keyvalue_to_text(summary, sep="=", vsep="\n", isep=",")
-        Path(summary_filename).write_text(text)
+        Path(summary_filename).write_text(text, encoding="utf-8")
 
     def end_file_test(
         self, module, cwd, returncode, stdout, stderr, test_summary, timed_out=None
@@ -1084,7 +1084,7 @@ def report_for_dir(self, root: StrPath, directory: StrPath, test_files) -> str:
             "<th>Failed</th><th>Percent successful</th>"
             "</tr></thead><tbody>"
         )
-        with open(page_name, "w") as page:
+        with open(page_name, "w", encoding="utf-8") as page:
             page.write(head)
             page.write(tests_table_head)
             for test_file_name in test_files:
@@ -1093,7 +1093,9 @@ def report_for_dir(self, root: StrPath, directory: StrPath, test_files) -> str:
                     root, directory, test_file_name, "test_keyvalue_result.txt"
                 )
                 # if os.path.exists(summary_filename):
-                summary = text_to_keyvalue(Path(summary_filename).read_text(), sep="=")
+                summary = text_to_keyvalue(
+                    Path(summary_filename).read_text(encoding="utf-8"), sep="="
+                )
                 # else:
                 # TODO: write else here
                 #    summary = None
@@ -1253,7 +1255,7 @@ def report_for_dirs(self, root: StrPath, directories) -> None:
             )
         )
 
-        with open(page_name, "w") as page:
+        with open(page_name, "w", encoding="utf-8") as page:
             page.write(head)
             page.write(tests_table_head)
 
diff --git a/python/grass/gunittest/utils.py b/python/grass/gunittest/utils.py
index 5c6481eb892..3fce4bb3299 100644
--- a/python/grass/gunittest/utils.py
+++ b/python/grass/gunittest/utils.py
@@ -33,7 +33,7 @@ def ensure_dir(directory: StrOrBytesPath) -> None:
 def add_gitignore_to_dir(directory: StrPath) -> None:
     gitignore_path = Path(directory) / ".gitignore"
     if not Path(gitignore_path).exists():
-        Path(gitignore_path).write_text("*")
+        Path(gitignore_path).write_text("*", encoding="utf-8")
 
 
 def silent_rmtree(filename: StrOrBytesPath) -> None: