diff --git a/pyproject.toml b/pyproject.toml
index 92fcc808..acc938ac 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -38,8 +38,9 @@ dependencies = [
 
 
 [project.optional-dependencies]
-test = ["pytest>=7", "waitress", "bcrypt"]
+test = ["pytest>=7", "waitress", "bcrypt", "argon2-cffi"]
 bcrypt = ["bcrypt"]
+argon2 = ["argon2-cffi"]
 ldap = ["ldap3"]
 
 [project.scripts]
diff --git a/radicale/auth/htpasswd.py b/radicale/auth/htpasswd.py
index 17dc2c9c..07f0b0fe 100644
--- a/radicale/auth/htpasswd.py
+++ b/radicale/auth/htpasswd.py
@@ -46,6 +46,9 @@ out-of-the-box:
 When bcrypt is installed:
     - BCRYPT     (htpasswd -B ...) -- Requires htpasswd 2.4.x
 
+When argon2 is installed:
+    - ARGON2     (python -c 'from passlib.hash import argon2; print(argon2.using(type="ID").hash("password"))')
+
 """
 
 import functools
@@ -72,8 +75,10 @@ class Auth(auth.BaseAuth):
     _htpasswd_not_ok_time: float
     _htpasswd_not_ok_reminder_seconds: int
     _htpasswd_bcrypt_use: int
+    _htpasswd_argon2_use: int
     _htpasswd_cache: bool
     _has_bcrypt: bool
+    _has_argon2: bool
     _encryption: str
     _lock: threading.Lock
 
@@ -89,9 +94,10 @@ class Auth(auth.BaseAuth):
         logger.info("auth htpasswd encryption is 'radicale.auth.htpasswd_encryption.%s'", self._encryption)
 
         self._has_bcrypt = False
+        self._has_argon2 = False
         self._htpasswd_ok = False
         self._htpasswd_not_ok_reminder_seconds = 60 # currently hardcoded
-        (self._htpasswd_ok, self._htpasswd_bcrypt_use, self._htpasswd, self._htpasswd_size, self._htpasswd_mtime_ns) = self._read_htpasswd(True, False)
+        (self._htpasswd_ok, self._htpasswd_bcrypt_use, self._htpasswd_argon2_use, self._htpasswd, self._htpasswd_size, self._htpasswd_mtime_ns) = self._read_htpasswd(True, False)
         self._lock = threading.Lock()
 
         if self._encryption == "plain":
@@ -102,7 +108,8 @@ class Auth(auth.BaseAuth):
             self._verify = self._sha256
         elif self._encryption == "sha512":
             self._verify = self._sha512
-        elif self._encryption == "bcrypt" or self._encryption == "autodetect":
+
+        if self._encryption == "bcrypt" or self._encryption == "autodetect":
             try:
                 import bcrypt
             except ImportError as e:
@@ -125,7 +132,33 @@ class Auth(auth.BaseAuth):
                 self._verify = self._autodetect
                 if self._htpasswd_bcrypt_use:
                     self._verify_bcrypt = functools.partial(self._bcrypt, bcrypt)
-        else:
+
+        if self._encryption == "argon2" or self._encryption == "autodetect":
+            try:
+                import argon2
+                from passlib.hash import argon2  # noqa: F811
+            except ImportError as e:
+                if (self._encryption == "autodetect") and (self._htpasswd_argon2_use == 0):
+                    logger.warning("auth htpasswd encryption is 'radicale.auth.htpasswd_encryption.%s' which can require argon2 module, but currently no entries found", self._encryption)
+                else:
+                    raise RuntimeError(
+                        "The htpasswd encryption method 'argon2' or 'autodetect' requires "
+                        "the argon2 module (entries found: %d)." % self._htpasswd_argon2_use) from e
+            else:
+                self._has_argon2 = True
+                if self._encryption == "autodetect":
+                    if self._htpasswd_argon2_use == 0:
+                        logger.info("auth htpasswd encryption is 'radicale.auth.htpasswd_encryption.%s' and argon2 module found, but currently not required", self._encryption)
+                    else:
+                        logger.info("auth htpasswd encryption is 'radicale.auth.htpasswd_encryption.%s' and argon2 module found (argon2 entries found: %d)", self._encryption, self._htpasswd_argon2_use)
+            if self._encryption == "argon2":
+                self._verify = functools.partial(self._argon2, argon2)
+            else:
+                self._verify = self._autodetect
+                if self._htpasswd_argon2_use:
+                    self._verify_argon2 = functools.partial(self._argon2, argon2)
+
+        if not hasattr(self, '_verify'):
             raise RuntimeError("The htpasswd encryption method %r is not "
                                "supported." % self._encryption)
 
@@ -144,6 +177,9 @@ class Auth(auth.BaseAuth):
         else:
             return ("BCRYPT", bcrypt.checkpw(password=password.encode('utf-8'), hashed_password=hash_value.encode()))
 
+    def _argon2(self, argon2: Any, hash_value: str, password: str) -> tuple[str, bool]:
+        return ("ARGON2", argon2.verify(password, hash_value.strip()))
+
     def _md5apr1(self, hash_value: str, password: str) -> tuple[str, bool]:
         if self._encryption == "autodetect" and len(hash_value) != 37:
             return self._plain_fallback("MD5-APR1", hash_value, password)
@@ -169,6 +205,9 @@ class Auth(auth.BaseAuth):
         elif re.match(r"^\$2(a|b|x|y)?\$", hash_value):
             # BCRYPT
             return self._verify_bcrypt(hash_value, password)
+        elif re.match(r"^\$argon2(i|d|id)\$", hash_value):
+            # ARGON2
+            return self._verify_argon2(hash_value, password)
         elif hash_value.startswith("$5$", 0, 3):
             # SHA-256
             return self._sha256(hash_value, password)
@@ -178,7 +217,7 @@ class Auth(auth.BaseAuth):
         else:
             return self._plain(hash_value, password)
 
-    def _read_htpasswd(self, init: bool, suppress: bool) -> Tuple[bool, int, dict, int, int]:
+    def _read_htpasswd(self, init: bool, suppress: bool) -> Tuple[bool, int, int, dict, int, int]:
         """Read htpasswd file
 
         init == True: stop on error
@@ -189,6 +228,7 @@ class Auth(auth.BaseAuth):
         """
         htpasswd_ok = True
         bcrypt_use = 0
+        argon2_use = 0
         if (init is True) or (suppress is True):
             info = "Read"
         else:
@@ -237,6 +277,14 @@ class Auth(auth.BaseAuth):
                                                 logger.warning("htpasswd file contains bcrypt digest login: '%s' (line: %d / ignored because module is not loaded)", login, line_num)
                                                 skip = True
                                                 htpasswd_ok = False
+                                    if re.match(r"^\$argon2(i|d|id)\$", digest):
+                                        if init is True:
+                                            argon2_use += 1
+                                        else:
+                                            if self._has_argon2 is False:
+                                                logger.warning("htpasswd file contains argon2 digest login: '%s' (line: %d / ignored because module is not loaded)", login, line_num)
+                                                skip = True
+                                                htpasswd_ok = False
                             if skip is False:
                                 htpasswd[login] = digest
                                 entries += 1
@@ -259,7 +307,7 @@ class Auth(auth.BaseAuth):
             self._htpasswd_not_ok_time = 0
         else:
             self._htpasswd_not_ok_time = time.time()
-        return (htpasswd_ok, bcrypt_use, htpasswd, htpasswd_size, htpasswd_mtime_ns)
+        return (htpasswd_ok, bcrypt_use, argon2_use, htpasswd, htpasswd_size, htpasswd_mtime_ns)
 
     def _login(self, login: str, password: str) -> str:
         """Validate credentials.
@@ -280,7 +328,7 @@ class Auth(auth.BaseAuth):
                 htpasswd_size = os.stat(self._filename).st_size
                 htpasswd_mtime_ns = os.stat(self._filename).st_mtime_ns
                 if (htpasswd_size != self._htpasswd_size) or (htpasswd_mtime_ns != self._htpasswd_mtime_ns):
-                    (self._htpasswd_ok, self._htpasswd_bcrypt_use, self._htpasswd, self._htpasswd_size, self._htpasswd_mtime_ns) = self._read_htpasswd(False, False)
+                    (self._htpasswd_ok, self._htpasswd_bcrypt_use, self._htpasswd_argon2_use, self._htpasswd, self._htpasswd_size, self._htpasswd_mtime_ns) = self._read_htpasswd(False, False)
                     self._htpasswd_not_ok_time = 0
 
             # log reminder of problemantic file every interval
@@ -298,7 +346,7 @@ class Auth(auth.BaseAuth):
                 login_ok = True
         else:
             # read file on every request
-            (htpasswd_ok, htpasswd_bcrypt_use, htpasswd, htpasswd_size, htpasswd_mtime_ns) = self._read_htpasswd(False, True)
+            (htpasswd_ok, htpasswd_bcrypt_use, htpasswd_argon2_use, htpasswd, htpasswd_size, htpasswd_mtime_ns) = self._read_htpasswd(False, True)
             if htpasswd.get(login):
                 digest = htpasswd[login]
                 login_ok = True
@@ -307,7 +355,7 @@ class Auth(auth.BaseAuth):
             try:
                 (method, password_ok) = self._verify(digest, password)
             except ValueError as e:
-                logger.error("Login verification failed for user: '%s' (htpasswd/%s) with errror '%s'", login, self._encryption, e)
+                logger.error("Login verification failed for user: '%s' (htpasswd/%s) with error '%s'", login, self._encryption, e)
                 return ""
             if password_ok:
                 logger.debug("Login verification successful for user: '%s' (htpasswd/%s/%s)", login, self._encryption, method)
diff --git a/radicale/tests/test_auth.py b/radicale/tests/test_auth.py
index b712e13d..88cd3ea4 100644
--- a/radicale/tests/test_auth.py
+++ b/radicale/tests/test_auth.py
@@ -49,6 +49,15 @@ class TestBaseAuthRequests(BaseTest):
     else:
         has_bcrypt = 1
 
+    # test for available argon2 module
+    try:
+        import argon2
+        from passlib.hash import argon2  # noqa: F811
+    except ImportError:
+        has_argon2 = 0
+    else:
+        has_argon2 = 1
+
     def _test_htpasswd(self, htpasswd_encryption: str, htpasswd_content: str,
                        test_matrix: Union[str, Iterable[Tuple[str, str, bool]]]
                        = "ascii") -> None:
@@ -147,6 +156,18 @@ class TestBaseAuthRequests(BaseTest):
     def test_htpasswd_bcrypt_unicode(self) -> None:
         self._test_htpasswd("bcrypt", "😀:$2y$10$Oyz5aHV4MD9eQJbk6GPemOs4T6edK6U9Sqlzr.W1mMVCS8wJUftnW", "unicode")
 
+    @pytest.mark.skipif(has_argon2 == 0, reason="No argon2 module installed")
+    def test_htpasswd_argon2_i(self) -> None:
+        self._test_htpasswd("argon2", "tmp:$argon2i$v=19$m=65536,t=3,p=4$NgZg7F1rzRkDoNSaMwag9A$qmsvMKEn5zOXHm8e3O5fKzzcRo0UESwaDr/cETe5YPI")
+
+    @pytest.mark.skipif(has_argon2 == 0, reason="No argon2 module installed")
+    def test_htpasswd_argon2_d(self) -> None:
+        self._test_htpasswd("argon2", "tmp:$argon2d$v=19$m=65536,t=3,p=4$ufe+txYiJKR0zlkLwVirVQ$MjGqRyVLes38hA6CEOkloMcTYCuLjxCKgIjtfYZ3iSM")
+
+    @pytest.mark.skipif(has_argon2 == 0, reason="No argon2 module installed")
+    def test_htpasswd_argon2_id(self) -> None:
+        self._test_htpasswd("argon2", "tmp:$argon2id$v=19$m=65536,t=3,p=4$t7bWuneOkdIa45xTqjXGmA$ORnRJyz9kHogJs6bDgZrTBPlzi4+p023PSEABb3xX1g")
+
     def test_htpasswd_multi(self) -> None:
         self._test_htpasswd("plain", "ign:ign\ntmp:bepo")
 
diff --git a/radicale/utils.py b/radicale/utils.py
index 11f8ab17..e0ae92a0 100644
--- a/radicale/utils.py
+++ b/radicale/utils.py
@@ -29,6 +29,7 @@ _T_co = TypeVar("_T_co", covariant=True)
 
 RADICALE_MODULES: Sequence[str] = ("radicale", "vobject", "passlib", "defusedxml",
                                    "bcrypt",
+                                   "argon2-cffi",
                                    "pika",
                                    "ldap",
                                    "ldap3",
diff --git a/setup.py.legacy b/setup.py.legacy
index ea446b39..be49627b 100644
--- a/setup.py.legacy
+++ b/setup.py.legacy
@@ -41,8 +41,9 @@ install_requires = ["defusedxml", "passlib", "vobject>=0.9.6",
                     "requests",
                     ]
 bcrypt_requires = ["bcrypt"]
+argon2_requires = ["argon2-cffi"]
 ldap_requires = ["ldap3"]
-test_requires = ["pytest>=7", "waitress", *bcrypt_requires]
+test_requires = ["pytest>=7", "waitress", *bcrypt_requires, *argon2_requires]
 
 setup(
     name="Radicale",
@@ -60,7 +61,7 @@ setup(
     package_data={"radicale": [*web_files, "py.typed"]},
     entry_points={"console_scripts": ["radicale = radicale.__main__:run"]},
     install_requires=install_requires,
-    extras_require={"test": test_requires, "bcrypt": bcrypt_requires, "ldap": ldap_requires},
+    extras_require={"test": test_requires, "bcrypt": bcrypt_requires, "argon2": argon2_requires, "ldap": ldap_requires},
     keywords=["calendar", "addressbook", "CalDAV", "CardDAV"],
     python_requires=">=3.9.0",
     classifiers=[