diff --git a/python/plugins/grassprovider/Grass7Utils.py b/python/plugins/grassprovider/Grass7Utils.py
index a7f95b0850a5..798c50af1900 100644
--- a/python/plugins/grassprovider/Grass7Utils.py
+++ b/python/plugins/grassprovider/Grass7Utils.py
@@ -91,7 +91,7 @@ def exportCrsWktToFile(crs):
         """
         wkt = crs.toWkt(QgsCoordinateReferenceSystem.WKT_PREFERRED)
         wkt_file = QgsProcessingUtils.generateTempFilename('crs.prj')
-        with open(wkt_file, 'wt') as f:
+        with open(wkt_file, 'wt', encoding='utf-8') as f:
             f.write(wkt)
         return wkt_file
 
diff --git a/python/plugins/processing/algs/gdal/extractprojection.py b/python/plugins/processing/algs/gdal/extractprojection.py
index c9b0877d16cf..7e128611d1ba 100644
--- a/python/plugins/processing/algs/gdal/extractprojection.py
+++ b/python/plugins/processing/algs/gdal/extractprojection.py
@@ -110,7 +110,7 @@ def processAlgorithm(self, parameters, context, feedback):
             crs = tmp.ExportToWkt()
             tmp = None
 
-            with open(outFileName + '.prj', 'wt') as prj:
+            with open(outFileName + '.prj', 'wt', encoding='utf-8') as prj:
                 prj.write(crs)
             results[self.PRJ_FILE] = outFileName + '.prj'
         else:
diff --git a/python/plugins/processing/algs/qgis/DefineProjection.py b/python/plugins/processing/algs/qgis/DefineProjection.py
index 42d6ed8892d0..97301b28cee8 100644
--- a/python/plugins/processing/algs/qgis/DefineProjection.py
+++ b/python/plugins/processing/algs/qgis/DefineProjection.py
@@ -85,7 +85,7 @@ def processAlgorithm(self, parameters, context, feedback):
             dsPath = dsPath[:-4]
 
             wkt = crs.toWkt(QgsCoordinateReferenceSystem.WKT1_ESRI)
-            with open(dsPath + '.prj', 'w') as f:
+            with open(dsPath + '.prj', 'wt', encoding='utf-8') as f:
                 f.write(wkt)
 
             qpjFile = dsPath + '.qpj'
diff --git a/python/plugins/sagaprovider/SagaAlgorithm.py b/python/plugins/sagaprovider/SagaAlgorithm.py
index 6f44714da3a4..1ecd1f701a3c 100644
--- a/python/plugins/sagaprovider/SagaAlgorithm.py
+++ b/python/plugins/sagaprovider/SagaAlgorithm.py
@@ -348,7 +348,7 @@ def processAlgorithm(self, parameters, context, feedback):
         if crs is not None:
             for out in output_layers:
                 prjFile = os.path.splitext(out)[0] + '.prj'
-                with open(prjFile, 'w') as f:
+                with open(prjFile, 'wt', encoding='utf-8') as f:
                     f.write(crs.toWkt())
 
         for old, new in output_files_nonascii.items():