diff --git a/aiida/cmdline/utils/echo.py b/aiida/cmdline/utils/echo.py
index be0227400d..133ace8668 100644
--- a/aiida/cmdline/utils/echo.py
+++ b/aiida/cmdline/utils/echo.py
@@ -10,6 +10,7 @@
 """Convenience functions for logging output from ``verdi`` commands."""
 import collections
 import enum
+import json
 import sys
 
 import click
@@ -207,7 +208,6 @@ def echo_formatted_list(collection, attributes, sort=None, highlight=None, hide=
 
 def _format_dictionary_json_date(dictionary, sort_keys=True):
     """Return a dictionary formatted as a string using the json format and converting dates to strings."""
-    from aiida.common import json
 
     def default_jsondump(data):
         """Function needed to decode datetimes, that would otherwise not be JSON-decodable."""
diff --git a/aiida/common/json.py b/aiida/common/json.py
index c58ff58669..7151ded476 100644
--- a/aiida/common/json.py
+++ b/aiida/common/json.py
@@ -7,65 +7,73 @@
 # For further information on the license, see the LICENSE.txt file        #
 # For further information please visit http://www.aiida.net               #
 ###########################################################################
-"""
-Abstracts JSON usage to ensure compatibility with Python2 and Python3.
+"""Abstracts JSON usage to ensure compatibility with Python2 and Python3.
 
 Use this module prefentially over standard json to ensure compatibility.
 
+.. deprecated:: This module is deprecated in v2.0.0 and should no longer be used. Python 2 support has long since been
+    dropped and for Python 3, one should simply use the ``json`` module of the standard library directly.
+
 """
-import simplejson
+import codecs
+import json
+import warnings
 
-JSONEncoder = simplejson.JSONEncoder
+from aiida.common.warnings import AiidaDeprecationWarning
 
+warnings.warn(
+    'This module has been deprecated and should no longer be used. Use the `json` standard library instead.',
+    AiidaDeprecationWarning
+)
 
-def dump(data, fhandle, **kwargs):
-    """
-    Write JSON encoded 'data' to a file-like object, fhandle
-    Use open(filename, 'wb') to write.
-    The utf8write object is used to ensure that the resulting serialised data is
-    encoding as UTF8.
-    Any strings with non-ASCII characters need to be unicode strings.
-    We use ensure_ascii=False to write unicode characters specifically
-    as this improves the readability of the json and reduces the file size.
-    """
-    import codecs
-    utf8writer = codecs.getwriter('utf8')
-    simplejson.dump(data, utf8writer(fhandle), ensure_ascii=False, encoding='utf8', **kwargs)
 
+def dump(data, handle, **kwargs):
+    """Serialize ``data`` as a JSON formatted stream to ``handle``.
 
-def dumps(data, **kwargs):
-    """
-    Write JSON encoded 'data' to a string.
-    simplejson is useful here as it always returns unicode if ensure_ascii=False is used,
-    unlike the standard library json, rather than being dependant on the input.
-    We use also ensure_ascii=False to write unicode characters specifically
-    as this improves the readability of the json and reduces the file size.
-    When writing to file, use open(filename, 'w', encoding='utf8')
+    We use ``ensure_ascii=False`` to write unicode characters specifically as this improves the readability of the json
+    and reduces the file size.
     """
-    return simplejson.dumps(data, ensure_ascii=False, encoding='utf8', **kwargs)
+    try:
+        if 'b' in handle.mode:
+            handle = codecs.getwriter('utf-8')(handle)
+    except AttributeError:
+        pass
 
+    return json.dump(data, handle, ensure_ascii=False, **kwargs)
 
-def load(fhandle, **kwargs):
+
+def dumps(data, **kwargs):
+    """Serialize ``data`` as a JSON formatted string.
+
+    We use ``ensure_ascii=False`` to write unicode characters specifically as this improves the readability of the json
+    and reduces the file size.
     """
-    Deserialise a JSON file.
+    return json.dumps(data, ensure_ascii=False, **kwargs)
+
 
-    For encoding consistency, open(filename, 'r', encoding='utf8') should be used.
+def load(handle, **kwargs):
+    """Deserialize ``handle`` text or binary file containing a JSON document to a Python object.
 
-    :raises ValueError: if no valid JSON object could be decoded
+    :raises ValueError: if no valid JSON object could be decoded.
     """
+    if 'b' in handle.mode:
+        handle = codecs.getreader('utf-8')(handle)
+
     try:
-        return simplejson.load(fhandle, encoding='utf8', **kwargs)
-    except simplejson.errors.JSONDecodeError:
-        raise ValueError
+        return json.load(handle, **kwargs)
+    except json.JSONDecodeError as exc:
+        raise ValueError from exc
 
 
-def loads(json_string, **kwargs):
-    """
-    Deserialise a JSON string.
+def loads(string, **kwargs):
+    """Deserialize text or binary ``string`` containing a JSON document to a Python object.
 
-    :raises ValueError: if no valid JSON object could be decoded
+    :raises ValueError: if no valid JSON object could be decoded.
     """
+    if isinstance(string, bytes):
+        string = string.decode('utf-8')
+
     try:
-        return simplejson.loads(json_string, encoding='utf8', **kwargs)
-    except simplejson.errors.JSONDecodeError:
-        raise ValueError
+        return json.loads(string, **kwargs)
+    except json.JSONDecodeError as exc:
+        raise ValueError from exc
diff --git a/aiida/engine/processes/calcjobs/calcjob.py b/aiida/engine/processes/calcjobs/calcjob.py
index 86c31ae3b8..92384572a3 100644
--- a/aiida/engine/processes/calcjobs/calcjob.py
+++ b/aiida/engine/processes/calcjobs/calcjob.py
@@ -9,6 +9,7 @@
 ###########################################################################
 """Implementation of the CalcJob process."""
 import io
+import json
 import os
 import shutil
 from typing import Any, Dict, Hashable, Optional, Type, Union
@@ -582,7 +583,6 @@ def presubmit(self, folder: Folder) -> CalcInfo:
 
         """
         # pylint: disable=too-many-locals,too-many-statements,too-many-branches
-        from aiida.common import json
         from aiida.common.datastructures import CodeInfo, CodeRunMode
         from aiida.common.exceptions import InputValidationError, InvalidOperation, PluginInternalError, ValidationError
         from aiida.common.utils import validate_list_of_string_tuples
diff --git a/aiida/manage/configuration/config.py b/aiida/manage/configuration/config.py
index 85b7123cfe..4b444ac288 100644
--- a/aiida/manage/configuration/config.py
+++ b/aiida/manage/configuration/config.py
@@ -8,8 +8,10 @@
 # For further information please visit http://www.aiida.net               #
 ###########################################################################
 """Module that defines the configuration file of an AiiDA instance and functions to create and load it."""
+import codecs
 from functools import lru_cache
 from importlib import resources
+import json
 import os
 import shutil
 import tempfile
@@ -17,7 +19,6 @@
 
 import jsonschema
 
-from aiida.common import json
 from aiida.common.exceptions import ConfigurationError
 
 from . import schema as schema_module
@@ -81,7 +82,7 @@ def from_file(cls, filepath):
         from .migrations import check_and_migrate_config, config_needs_migrating
 
         try:
-            with open(filepath, 'r', encoding='utf8') as handle:
+            with open(filepath, 'rb') as handle:
                 config = json.load(handle)
         except FileNotFoundError:
             config = Config(filepath, check_and_migrate_config({}))
@@ -492,7 +493,7 @@ def store(self):
         # Otherwise, we write the content to a temporary file and compare its md5 checksum with the current config on
         # disk. When the checksums differ, we first create a backup and only then overwrite the existing file.
         with tempfile.NamedTemporaryFile() as handle:
-            json.dump(self.dictionary, handle, indent=DEFAULT_CONFIG_INDENT_SIZE)
+            json.dump(self.dictionary, codecs.getwriter('utf-8')(handle), indent=DEFAULT_CONFIG_INDENT_SIZE)
             handle.seek(0)
 
             if md5_from_filelike(handle) != md5_file(self.filepath):
@@ -522,7 +523,7 @@ def _atomic_write(self, filepath=None):
         # Create a temporary file in the same directory as the target filepath, which guarantees that the temporary
         # file is on the same filesystem, which is necessary to be able to use ``os.rename``. Since we are moving the
         # temporary file, we should also tell the tempfile to not be automatically deleted as that will raise.
-        with tempfile.NamedTemporaryFile(dir=os.path.dirname(filepath), delete=False) as handle:
+        with tempfile.NamedTemporaryFile(dir=os.path.dirname(filepath), delete=False, mode='w') as handle:
             try:
                 json.dump(self.dictionary, handle, indent=DEFAULT_CONFIG_INDENT_SIZE)
             finally:
diff --git a/aiida/orm/implementation/utils.py b/aiida/orm/implementation/utils.py
index 54a6a4bb62..76791336c2 100644
--- a/aiida/orm/implementation/utils.py
+++ b/aiida/orm/implementation/utils.py
@@ -63,7 +63,7 @@ def clean_builtin(val):
         It mainly checks that we don't store NaN or Inf.
         """
         # This is a whitelist of all the things we understand currently
-        if val is None or isinstance(val, (bool, str, Decimal)):
+        if val is None or isinstance(val, (bool, str)):
             return val
 
         # This fixes #2773 - in python3, ``numpy.int64(-1)`` cannot be json-serialized
@@ -77,7 +77,7 @@ def clean_builtin(val):
 
         # This is for float-like types, like ``numpy.float128`` that are not json-serializable
         # Note that `numbers.Real` also match booleans but they are already returned above
-        if isinstance(val, numbers.Real):
+        if isinstance(val, (numbers.Real, Decimal)):
             string_representation = f'{{:.{AIIDA_FLOAT_PRECISION}g}}'.format(val)
             new_val = float(string_representation)
             if 'e' in string_representation and new_val.is_integer():
diff --git a/aiida/orm/nodes/data/array/bands.py b/aiida/orm/nodes/data/array/bands.py
index dfb8d4b22f..c47f96afb8 100644
--- a/aiida/orm/nodes/data/array/bands.py
+++ b/aiida/orm/nodes/data/array/bands.py
@@ -12,6 +12,7 @@
 This module defines the classes related to band structures or dispersions
 in a Brillouin zone, and how to operate on them.
 """
+import json
 from string import Template
 
 import numpy
@@ -811,8 +812,6 @@ def _prepare_mpl_singlefile(self, *args, **kwargs):
         For the possible parameters, see documentation of
         :py:meth:`~aiida.orm.nodes.data.array.bands.BandsData._matplotlib_get_dict`
         """
-        from aiida.common import json
-
         all_data = self._matplotlib_get_dict(*args, **kwargs)
 
         s_header = MATPLOTLIB_HEADER_TEMPLATE.substitute()
@@ -834,8 +833,6 @@ def _prepare_mpl_withjson(self, main_file_name='', *args, **kwargs):  # pylint:
         """
         import os
 
-        from aiida.common import json
-
         all_data = self._matplotlib_get_dict(*args, main_file_name=main_file_name, **kwargs)
 
         json_fname = os.path.splitext(main_file_name)[0] + '_data.json'
@@ -866,8 +863,6 @@ def _prepare_mpl_pdf(self, main_file_name='', *args, **kwargs):  # pylint: disab
         import sys
         import tempfile
 
-        from aiida.common import json
-
         all_data = self._matplotlib_get_dict(*args, **kwargs)
 
         # Use the Agg backend
@@ -911,7 +906,6 @@ def _prepare_mpl_png(self, main_file_name='', *args, **kwargs):  # pylint: disab
         For the possible parameters, see documentation of
         :py:meth:`~aiida.orm.nodes.data.array.bands.BandsData._matplotlib_get_dict`
         """
-        import json
         import os
         import subprocess
         import sys
@@ -1237,7 +1231,6 @@ def _prepare_json(self, main_file_name='', comments=True):  # pylint: disable=un
             format)
         """
         from aiida import get_file_header
-        from aiida.common import json
 
         json_dict = self._get_band_segments(cartesian=True)
         json_dict['original_uuid'] = self.uuid
diff --git a/aiida/orm/nodes/data/structure.py b/aiida/orm/nodes/data/structure.py
index b65b736ced..700cb5f4f6 100644
--- a/aiida/orm/nodes/data/structure.py
+++ b/aiida/orm/nodes/data/structure.py
@@ -15,6 +15,7 @@
 import copy
 import functools
 import itertools
+import json
 
 from aiida.common.constants import elements
 from aiida.common.exceptions import UnsupportedSpeciesError
@@ -1016,8 +1017,6 @@ def _prepare_chemdoodle(self, main_file_name=''):  # pylint: disable=unused-argu
 
         import numpy as np
 
-        from aiida.common import json
-
         supercell_factors = [1, 1, 1]
 
         # Get cell vectors and atomic position
diff --git a/aiida/restapi/translator/nodes/data/array/bands.py b/aiida/restapi/translator/nodes/data/array/bands.py
index 5b023c4026..87f1d6542d 100644
--- a/aiida/restapi/translator/nodes/data/array/bands.py
+++ b/aiida/restapi/translator/nodes/data/array/bands.py
@@ -10,6 +10,7 @@
 """
 Translator for bands data
 """
+import json
 
 from aiida.restapi.translator.nodes.data import DataTranslator
 
@@ -44,7 +45,6 @@ def get_derived_properties(node):
         """
         response = {}
 
-        from aiida.common import json
         json_string = node._exportcontent('json', comments=False)  # pylint: disable=protected-access
         json_content = json.loads(json_string[0])
         response['bands'] = json_content
diff --git a/aiida/schedulers/datastructures.py b/aiida/schedulers/datastructures.py
index 2ca464f925..b788724ed4 100644
--- a/aiida/schedulers/datastructures.py
+++ b/aiida/schedulers/datastructures.py
@@ -16,6 +16,7 @@
 """
 import abc
 import enum
+import json
 
 from aiida.common import AIIDA_LOGGER
 from aiida.common.extendeddicts import AttributeDict, DefaultFieldsAttributeDict
@@ -543,8 +544,6 @@ def serialize(self):
 
         :return: A string with serialised representation of the current data.
         """
-        from aiida.common import json
-
         return json.dumps(self.get_dict())
 
     def get_dict(self):
@@ -574,6 +573,4 @@ def load_from_serialized(cls, data):
 
         :param data: The string with the JSON-serialised data to load from
         """
-        from aiida.common import json
-
         return cls.load_from_dict(json.loads(data))
diff --git a/aiida/storage/psql_dos/migrations/utils/create_dbattribute.py b/aiida/storage/psql_dos/migrations/utils/create_dbattribute.py
index 54ce1dac8b..0682d016f4 100644
--- a/aiida/storage/psql_dos/migrations/utils/create_dbattribute.py
+++ b/aiida/storage/psql_dos/migrations/utils/create_dbattribute.py
@@ -14,8 +14,8 @@
 from __future__ import annotations
 
 import datetime
+import json
 
-from aiida.common import json
 from aiida.common.exceptions import ValidationError
 from aiida.common.timezone import get_current_timezone, is_naive, make_aware
 
diff --git a/aiida/storage/psql_dos/migrations/utils/legacy_workflows.py b/aiida/storage/psql_dos/migrations/utils/legacy_workflows.py
index 92bcb4f95e..53dd8cdd6d 100644
--- a/aiida/storage/psql_dos/migrations/utils/legacy_workflows.py
+++ b/aiida/storage/psql_dos/migrations/utils/legacy_workflows.py
@@ -9,13 +9,14 @@
 ###########################################################################
 # pylint: disable=invalid-name
 """Utilities for removing legacy workflows."""
+import codecs
+import json
 import sys
 
 import click
 from sqlalchemy.sql import func, select, table
 
 from aiida.cmdline.utils import echo
-from aiida.common import json
 
 
 def json_serializer(obj):
@@ -70,7 +71,7 @@ def export_workflow_data(connection, profile):
         prefix='legacy-workflows', suffix='.json', dir='.', delete=delete_on_close, mode='wb'
     ) as handle:
         filename = handle.name
-        json.dump(data, handle, default=json_serializer)
+        json.dump(data, codecs.getwriter('utf-8')(handle), default=json_serializer)
 
     # If delete_on_close is False, we are running for the user and add additional message of file location
     if not delete_on_close:
diff --git a/aiida/storage/psql_dos/migrations/utils/utils.py b/aiida/storage/psql_dos/migrations/utils/utils.py
index 89d2fc5cb9..7ce3cf3fe1 100644
--- a/aiida/storage/psql_dos/migrations/utils/utils.py
+++ b/aiida/storage/psql_dos/migrations/utils/utils.py
@@ -12,6 +12,7 @@
 import datetime
 import functools
 import io
+import json
 import os
 import pathlib
 import re
@@ -21,7 +22,7 @@
 from disk_objectstore.utils import LazyOpener
 import numpy
 
-from aiida.common import exceptions, json
+from aiida.common import exceptions
 from aiida.repository.backend import AbstractRepositoryBackend
 from aiida.repository.common import File, FileType
 from aiida.repository.repository import Repository
diff --git a/aiida/storage/psql_dos/utils.py b/aiida/storage/psql_dos/utils.py
index 7de46c4539..4d6be94335 100644
--- a/aiida/storage/psql_dos/utils.py
+++ b/aiida/storage/psql_dos/utils.py
@@ -9,6 +9,7 @@
 ###########################################################################
 # pylint: disable=import-error,no-name-in-module
 """Utility functions specific to the SqlAlchemy backend."""
+import json
 from typing import TypedDict
 
 
@@ -33,8 +34,6 @@ def create_sqlalchemy_engine(config: PsqlConfig):
     """
     from sqlalchemy import create_engine
 
-    from aiida.common import json
-
     # The hostname may be `None`, which is a valid value in the case of peer authentication for example. In this case
     # it should be converted to an empty string, because otherwise the `None` will be converted to string literal "None"
     hostname = config['database_hostname'] or ''
diff --git a/aiida/storage/sqlite_zip/migrator.py b/aiida/storage/sqlite_zip/migrator.py
index 52cd81a91a..281fe8e099 100644
--- a/aiida/storage/sqlite_zip/migrator.py
+++ b/aiida/storage/sqlite_zip/migrator.py
@@ -10,6 +10,7 @@
 """Versioning and migration implementation for the sqlite_zip format."""
 import contextlib
 from datetime import datetime
+import json
 import os
 from pathlib import Path
 import shutil
@@ -25,7 +26,6 @@
 from alembic.script import ScriptDirectory
 from archive_path import ZipPath, extract_file_in_zip, open_file_in_tar, open_file_in_zip
 
-from aiida.common import json
 from aiida.common.exceptions import CorruptStorage, IncompatibleStorageSchema, StorageMigrationError
 from aiida.common.progress_reporter import get_progress_reporter
 from aiida.storage.log import MIGRATE_LOGGER
diff --git a/aiida/storage/sqlite_zip/utils.py b/aiida/storage/sqlite_zip/utils.py
index cd2838314e..18ed4996cb 100644
--- a/aiida/storage/sqlite_zip/utils.py
+++ b/aiida/storage/sqlite_zip/utils.py
@@ -8,6 +8,7 @@
 # For further information please visit http://www.aiida.net               #
 ###########################################################################
 """Utilities for this backend."""
+import json
 from pathlib import Path
 import tarfile
 from typing import Any, Dict, Optional, Union
@@ -17,7 +18,6 @@
 from sqlalchemy import event
 from sqlalchemy.future.engine import Engine, create_engine
 
-from aiida.common import json
 from aiida.common.exceptions import CorruptStorage, UnreachableStorage
 
 META_FILENAME = 'metadata.json'
diff --git a/aiida/tools/dbimporters/plugins/mpds.py b/aiida/tools/dbimporters/plugins/mpds.py
index 3c12892105..52fd7b9439 100644
--- a/aiida/tools/dbimporters/plugins/mpds.py
+++ b/aiida/tools/dbimporters/plugins/mpds.py
@@ -10,11 +10,11 @@
 """"Implementation of `DbImporter` for the MPDS database."""
 import copy
 import enum
+import json
 import os
 
 import requests
 
-from aiida.common import json
 from aiida.tools.dbimporters.baseclasses import CifEntry, DbEntry, DbImporter, DbSearchResults
 
 
diff --git a/aiida/tools/ipython/ipython_magics.py b/aiida/tools/ipython/ipython_magics.py
index 494549416a..4e7110fd06 100644
--- a/aiida/tools/ipython/ipython_magics.py
+++ b/aiida/tools/ipython/ipython_magics.py
@@ -33,6 +33,7 @@
 
    In [2]: %aiida
 """
+import json
 
 from IPython import get_ipython, version_info
 from IPython.core import magic
@@ -97,8 +98,6 @@ def _repr_json_(self):
         """
         Output in JSON format.
         """
-        from aiida.common import json
-
         obj = {'current_state': self.current_state}
         if version_info[0] >= 3:
             return obj
diff --git a/environment.yml b/environment.yml
index 37fcb122e3..6c4143e1d4 100644
--- a/environment.yml
+++ b/environment.yml
@@ -30,7 +30,6 @@ dependencies:
 - python-dateutil~=2.8
 - pytz~=2021.1
 - pyyaml~=5.4
-- simplejson~=3.16
 - sqlalchemy~=1.4.22
 - tabulate~=0.8.5
 - tqdm~=4.45
diff --git a/pyproject.toml b/pyproject.toml
index e2185b306f..d9d5cf8060 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -48,7 +48,6 @@ dependencies = [
         "python-dateutil~=2.8",
         "pytz~=2021.1",
         "pyyaml~=5.4",
-        "simplejson~=3.16",
         "sqlalchemy~=1.4.22",
         "tabulate~=0.8.5",
         "tqdm~=4.45",
diff --git a/requirements/requirements-py-3.10.txt b/requirements/requirements-py-3.10.txt
index a044f49400..08d55f8435 100644
--- a/requirements/requirements-py-3.10.txt
+++ b/requirements/requirements-py-3.10.txt
@@ -133,7 +133,6 @@ seekpath==1.9.7
 Send2Trash==1.8.0
 setuptools-scm==6.3.2
 shortuuid==1.0.8
-simplejson==3.17.6
 six==1.16.0
 snowballstemmer==2.2.0
 soupsieve==2.3.1
diff --git a/requirements/requirements-py-3.8.txt b/requirements/requirements-py-3.8.txt
index be81f85218..6c35d8780c 100644
--- a/requirements/requirements-py-3.8.txt
+++ b/requirements/requirements-py-3.8.txt
@@ -135,7 +135,6 @@ seekpath==1.9.7
 Send2Trash==1.8.0
 setuptools-scm==6.3.2
 shortuuid==1.0.8
-simplejson==3.17.6
 six==1.16.0
 snowballstemmer==2.2.0
 soupsieve==2.3.1
diff --git a/requirements/requirements-py-3.9.txt b/requirements/requirements-py-3.9.txt
index 54b2c6afe0..ce0025c74b 100644
--- a/requirements/requirements-py-3.9.txt
+++ b/requirements/requirements-py-3.9.txt
@@ -134,7 +134,6 @@ seekpath==1.9.7
 Send2Trash==1.8.0
 setuptools-scm==6.3.2
 shortuuid==1.0.8
-simplejson==3.17.6
 six==1.16.0
 snowballstemmer==2.2.0
 soupsieve==2.3.1
diff --git a/tests/common/test_extendeddicts.py b/tests/common/test_extendeddicts.py
index 881ccd7a1d..6830f68a1c 100644
--- a/tests/common/test_extendeddicts.py
+++ b/tests/common/test_extendeddicts.py
@@ -9,12 +9,12 @@
 ###########################################################################
 """Tests for the extended dictionary classes."""
 # pylint: disable=pointless-statement,attribute-defined-outside-init
-
 import copy
+import json
 import pickle
 import unittest
 
-from aiida.common import exceptions, extendeddicts, json
+from aiida.common import exceptions, extendeddicts
 
 
 class FFADExample(extendeddicts.FixedFieldsAttributeDict):
diff --git a/tests/manage/configuration/migrations/test_migrations.py b/tests/manage/configuration/migrations/test_migrations.py
index 68c2b06336..3771c6cf3c 100644
--- a/tests/manage/configuration/migrations/test_migrations.py
+++ b/tests/manage/configuration/migrations/test_migrations.py
@@ -10,12 +10,12 @@
 # pylint: disable=redefined-outer-name
 """Tests for the configuration migration functionality."""
 import copy
+import json
 import pathlib
 import uuid
 
 import pytest
 
-from aiida.common import json
 from aiida.common.exceptions import ConfigurationError
 from aiida.manage.configuration.migrations import check_and_migrate_config
 from aiida.manage.configuration.migrations.migrations import MIGRATIONS, Initial, downgrade_config, upgrade_config
diff --git a/tests/manage/configuration/test_config.py b/tests/manage/configuration/test_config.py
index 17e2069f6d..e807946c4a 100644
--- a/tests/manage/configuration/test_config.py
+++ b/tests/manage/configuration/test_config.py
@@ -8,12 +8,13 @@
 # For further information please visit http://www.aiida.net               #
 ###########################################################################
 """Tests for the ``Config`` class."""
+import json
 import os
 import pathlib
 
 import pytest
 
-from aiida.common import exceptions, json
+from aiida.common import exceptions
 from aiida.manage.configuration import Config, Profile, settings
 from aiida.manage.configuration.migrations import CURRENT_CONFIG_VERSION, OLDEST_COMPATIBLE_CONFIG_VERSION
 from aiida.manage.configuration.options import get_option
diff --git a/tests/orm/test_logs.py b/tests/orm/test_logs.py
index 66f342ab61..1fee563ba8 100644
--- a/tests/orm/test_logs.py
+++ b/tests/orm/test_logs.py
@@ -9,6 +9,7 @@
 ###########################################################################
 # pylint: disable=no-self-use
 """ORM Log tests"""
+import json
 import logging
 
 import pytest
@@ -279,8 +280,6 @@ def test_raise_wrong_metadata_type_error(self):
         Test a TypeError exception is thrown with string metadata.
         Also test that metadata is correctly created.
         """
-        from aiida.common import json
-
         # Create CalculationNode
         calc = orm.CalculationNode().store()
 
diff --git a/tests/restapi/test_routes.py b/tests/restapi/test_routes.py
index 2d8252622d..220a6a0372 100644
--- a/tests/restapi/test_routes.py
+++ b/tests/restapi/test_routes.py
@@ -11,12 +11,12 @@
 """Unittests for REST API."""
 from datetime import date
 import io
+import json
 
 from flask_cors.core import ACL_ORIGIN
 import pytest
 
 from aiida import orm
-from aiida.common import json
 from aiida.common.links import LinkType
 from aiida.manage import get_manager
 from aiida.restapi.run_api import configure_api
diff --git a/tests/storage/psql_dos/migrations/django_branch/test_0033_replace_text_field_with_json_field.py b/tests/storage/psql_dos/migrations/django_branch/test_0033_replace_text_field_with_json_field.py
index db3d4e80b1..27082a8c9e 100644
--- a/tests/storage/psql_dos/migrations/django_branch/test_0033_replace_text_field_with_json_field.py
+++ b/tests/storage/psql_dos/migrations/django_branch/test_0033_replace_text_field_with_json_field.py
@@ -8,7 +8,9 @@
 # For further information please visit http://www.aiida.net               #
 ###########################################################################
 """Test migration adding the `repository_metadata` column to the `Node` model."""
-from aiida.common import json, timezone
+import json
+
+from aiida.common import timezone
 from aiida.common.utils import get_new_uuid
 from aiida.storage.psql_dos.migrator import PsqlDostoreMigrator
 
diff --git a/tests/tools/archive/test_simple.py b/tests/tools/archive/test_simple.py
index 43a58a1e7c..bee2df8468 100644
--- a/tests/tools/archive/test_simple.py
+++ b/tests/tools/archive/test_simple.py
@@ -8,11 +8,12 @@
 # For further information please visit http://www.aiida.net               #
 ###########################################################################
 """Simple tests for the export and import routines"""
+import json
+
 from archive_path import ZipPath
 import pytest
 
 from aiida import orm
-from aiida.common import json
 from aiida.common.exceptions import IncompatibleStorageSchema, LicensingException
 from aiida.common.links import LinkType
 from aiida.tools.archive import create_archive, import_archive
diff --git a/tests/utils/archives.py b/tests/utils/archives.py
index 8bb130c212..36f4ae87a9 100644
--- a/tests/utils/archives.py
+++ b/tests/utils/archives.py
@@ -8,6 +8,7 @@
 # For further information please visit http://www.aiida.net               #
 ###########################################################################
 """Test utility to import, inspect, or migrate AiiDA export archives."""
+import json
 import os
 import tarfile
 from typing import List
@@ -15,7 +16,6 @@
 
 from archive_path import read_file_in_tar, read_file_in_zip
 
-from aiida.common import json
 from tests.static import STATIC_DIR