diff --git a/local/lib/python3/cmk/base/plugins/agent_based/mailcow_domains.py b/local/lib/python3/cmk/base/plugins/agent_based/mailcow_domains.py
index 2a02743..f544ad5 100644
--- a/local/lib/python3/cmk/base/plugins/agent_based/mailcow_domains.py
+++ b/local/lib/python3/cmk/base/plugins/agent_based/mailcow_domains.py
@@ -42,8 +42,8 @@ def check_mailcow_domains(item, params, section):
     # create graph for used quota
     yield Metric("mailcow_domains_used_quota", percent_storage_used_for_messages, levels=levels)
 
-    summary_quota = f"Quota used is {render.percent(percent_storage_used_for_messages)}"
-    details_quota = f"Quota: {render.bytes(total_number_of_bytes_used)} of {render.bytes(quota)} used"
+    summary_quota = f"Storage quota used is {render.percent(percent_storage_used_for_messages)}"
+    details_quota = f"Storage quota: {render.bytes(total_number_of_bytes_used)} of {render.bytes(quota)} used"
  
     # create service
     yield(Result(state=state_quota, summary=summary_quota, details=details_quota))
@@ -112,19 +112,11 @@ def parse_mailcow_domains_section(string_table):
             create_time_data = "Not available"
         else:
             create_time_data = create_time_value
-            #create_time = int(create_time_value)
-            #curr_time = int(time.time())
-            #diff_time = curr_time - create_time
-            #create_time_data = render.timespan(diff_time)
         modify_time_value = line[3]
         if modify_time_value == "None":
             modify_time_data = "Never"
         else:
             modify_time_data = modify_time_value
-            #modify_time = int(modify_time_value)
-            #curr_time = int(time.time())
-            #diff_time = curr_time - modify_time
-            #modify_time_data = render.timespan(diff_time)
         # calculate percentage of used mailboxes
         max_number_of_mailboxes = int(line[4])
         number_of_mailboxes = int(line[5])
diff --git a/local/lib/python3/cmk/base/plugins/agent_based/mailcow_mailboxes.py b/local/lib/python3/cmk/base/plugins/agent_based/mailcow_mailboxes.py
new file mode 100644
index 0000000..8eebb78
--- /dev/null
+++ b/local/lib/python3/cmk/base/plugins/agent_based/mailcow_mailboxes.py
@@ -0,0 +1,148 @@
+#!/usr/bin/env python3
+import time
+import random
+from pprint import pprint
+from .agent_based_api.v1 import get_value_store, get_rate, register, render, Service, Result, State, Metric
+
+def getStateUpper(levels, value):
+    warn, crit = levels
+    if value >= crit:
+        return State.CRIT
+    if value >= warn:
+        return State.WARN
+    return State.OK
+
+def discover_mailcow_mailboxes(section):
+    for key in section:
+        yield(Service(item = key))
+
+def check_mailcow_mailboxes(item, params, section):
+    mailbox = item
+    # get all values from section
+    active = section[mailbox][0]
+    create_time = section[mailbox][1]
+    modify_time = section[mailbox][2]
+    display_name = section[mailbox][3]
+    number_of_messages = section[mailbox][4]
+    _percent_in_use = section[mailbox][5]
+    quota = section[mailbox][6]
+    total_number_of_bytes_used = section[mailbox][7]
+    percent_storage_used_for_messages = section[mailbox][8]
+    last_imap_login_data = section[mailbox][9]
+    last_pop3_login_data = section[mailbox][10]
+    last_smtp_login_data = section[mailbox][11]
+
+    # create (main) service for used storage (mailbox quota)
+    warn, crit = params["levels_mailcow_mailboxes_quota_used"]
+    levels = (warn, crit)
+    state_quota = getStateUpper(levels, percent_storage_used_for_messages)
+    # create graph for used quota
+    yield Metric("mailcow_mailboxes_used_quota", percent_storage_used_for_messages, levels=levels)
+    summary_quota = f"Storage quota for mailbox of '{display_name}' is {render.percent(percent_storage_used_for_messages)}"
+    details_quota = f"Quota: {render.bytes(total_number_of_bytes_used)} of {render.bytes(quota)} used"
+ 
+    # create service
+    yield(Result(state=state_quota, summary=summary_quota, details=details_quota))
+
+    # create some additional services and information only details
+    notice = f"Active: {active}"
+    yield(Result(state=State.OK, notice=notice))
+    notice = f"Creation date: {create_time}"
+    yield(Result(state=State.OK, notice=notice))
+    notice = f"Last modified: {modify_time}"
+    yield(Result(state=State.OK, notice=notice))
+
+    notice = f"Last IMAP login: {last_imap_login_data} ago"
+    yield(Result(state=State.OK, notice=notice))
+    notice = f"Last POP3 login: {last_pop3_login_data} ago"
+    yield(Result(state=State.OK, notice=notice))
+    notice = f"Last SMTP login: {last_smtp_login_data} ago"
+    yield(Result(state=State.OK, notice=notice))
+
+    # create service for number of messages
+    warn, crit = params["levels_mailcow_mailboxes_num_messages"]
+    levels = (warn, crit)
+    state_messages = getStateUpper(levels, number_of_messages)
+    yield Metric("mailcow_mailboxes_messages", number_of_messages, levels=levels)
+    notice = f"Number of messages: {number_of_messages}"
+    yield(Result(state=state_messages, notice=notice))
+
+ 
+def parse_mailcow_mailboxes_section(string_table):
+    # convert the raw output of the agent section into a meaningful structure, do type conversions and so on
+    parsed_data = {}
+    for line in string_table:
+        mailboxname = line[0]
+        value_active = int(line[1])
+        if value_active == 1:
+            active = "yes"
+        else:
+            active = "no"
+        # calculate creation and last modification date in human readable format
+        create_time_value = line[2]
+        if create_time_value == "None":
+            create_time_data = "Not available"
+        else:
+            create_time_data = create_time_value
+        modify_time_value = line[3]
+        if modify_time_value == "None":
+            modify_time_data = "Never"
+        else:
+            modify_time_data = modify_time_value
+        # get display name
+        display_name = line[4]
+        # number of messages within mailbox
+        number_of_messages = int(line[5])
+        # percent in use, rounded to full percent
+        percent_in_use = int(line[6])
+        # calculate storage used for all messages in mailbox
+        quota = int(line[7])
+        total_number_of_bytes_used = int(line[8])
+        percent_storage_used_for_messages = total_number_of_bytes_used * 100 / quota
+        # get time of last login for IMAP/POP3/SMTP (seconds since epoch)
+        last_imap_login = int(line[9])
+        last_pop3_login = int(line[10])
+        last_smtp_login = int(line[11])
+        # transfer these times into a human friendly format
+        if last_imap_login == 0:
+            last_imap_login_data = "Never"
+        else:
+            curr_time = int(time.time())
+            diff_time = curr_time - last_imap_login
+            last_imap_login_data = render.timespan(diff_time)
+        if last_pop3_login == 0:
+            last_pop3_login_data = "Never"
+        else:
+            curr_time = int(time.time())
+            diff_time = curr_time - last_pop3_login
+            last_pop3_login_data = render.timespan(diff_time)
+        if last_smtp_login == 0:
+            last_smtp_login_data = "Never"
+        else:
+            curr_time = int(time.time())
+            diff_time = curr_time - last_smtp_login
+            last_smtp_login_data = render.timespan(diff_time)
+        # store all (calculated) data
+        parsed_data[f"{mailboxname}"] = [active, create_time_data, modify_time_data,
+                                        display_name, number_of_messages, percent_in_use,
+                                        quota, total_number_of_bytes_used, percent_storage_used_for_messages,
+                                        last_imap_login_data, last_pop3_login_data, last_smtp_login_data
+                                       ]
+    return parsed_data
+      
+register.agent_section(
+    name = "mailcow_mailboxes",
+    parse_function = parse_mailcow_mailboxes_section,
+)
+
+register.check_plugin(
+    name = "mailcow_mailboxes",
+    service_name = "Mailcow mailbox %s",
+    discovery_function = discover_mailcow_mailboxes,
+    check_function = check_mailcow_mailboxes,
+    check_default_parameters = {
+        "levels_mailcow_mailboxes_quota_used": (65.0, 85.0),
+        "levels_mailcow_mailboxes_num_messages": (1000, 2500),
+    },
+    check_ruleset_name="mailcow_mailboxes",
+)
\ No newline at end of file
diff --git a/local/share/check_mk/agents/special/agent_mailcow b/local/share/check_mk/agents/special/agent_mailcow
index 7d1b7dc..f12d9d1 100755
--- a/local/share/check_mk/agents/special/agent_mailcow
+++ b/local/share/check_mk/agents/special/agent_mailcow
@@ -219,18 +219,18 @@ def getMailcowInfo(headers, verify, base_url):
 
 '''
 Output is as follows:
-mailbox name                email address used for login
-active                      1 --> active, 0 --> not active
-creation date               "None" if ???
-last modified date          "None" if never modified
-name                        display name
-number of messages
-percent in use              quota used, rounded to full percents
-quota                       max quota in bytes
-quota used                  quota used in bytes
-last imap login             seconds since epoch, 0 if never logged inin seconds since epoch
-last pop3 login             seconds since epoch, 0 if never logged in
-last smtp login             seconds since epoch, 0 if never logged in
+0   mailbox name                email address used for login
+1   active                      1 --> active, 0 --> not active
+2   creation date               "None" if ???
+3   last modified date          "None" if never modified
+4   name                        display name
+5   number of messages
+6   percent in use              quota used, rounded to full percents
+7   quota                       max quota in bytes
+8   quota used                  quota used in bytes
+9   last imap login             seconds since epoch, 0 if never logged in
+10  last pop3 login             seconds since epoch, 0 if never logged in
+11  last smtp login             seconds since epoch, 0 if never logged in
 
 Example:
 user1@dom1.de;1;2022-04-29 14:29:34;2022-04-29 14:29:34;Sarah;2433;2;21474836480;495481374;1692520168;0;1692281537
@@ -266,17 +266,17 @@ def doCmkOutputMailcow(version, num_domains, num_mailboxes, num_global_messages)
 
 '''
 Output is as follows:
-domain_name
-active                      1 --> active, 0 --> not active
-creation date               "None" if ???
-last modified date          "None" if never modified
-max number mailboxes
-number of mailboxes
-max number of aliases
-number of aliases
-total number of messages
-total number of bytes used  in bytes
-max quota                   in bytes
+0   domain_name
+1   active                      1 --> active, 0 --> not active
+2   creation date               "None" if ???
+3   last modified date          "None" if never modified
+4   max number mailboxes
+5   number of mailboxes
+6   max number of aliases
+7   number of aliases
+8   total number of messages
+9   total number of bytes used  in bytes
+10  max quota                   in bytes
 
 Example:
 dom1.de;1;2022-04-23 22:54:57;None;10;0;400;6;0;0;10737418240
diff --git a/local/share/check_mk/checkman/mailcow_mailboxes b/local/share/check_mk/checkman/mailcow_mailboxes
new file mode 100644
index 0000000..232b32e
--- /dev/null
+++ b/local/share/check_mk/checkman/mailcow_mailboxes
@@ -0,0 +1,18 @@
+title: Mailcow: Usage per Mailbox, Quota and Number of Messages
+agents: linux
+catalog: unsorted
+license: GPL
+distribution: check_mk
+description:
+ Tested with Mailcow versions 2022-07a and higher (use at your own risk with lower versions).
+ Tested only with fully dockerized Mailcow instances.
+ You have to provide at least the hostname/IP of your Mailcow server and an API key.
+ Got to configuration settings and create a new API key (read-only access is sufficient).
+ Allow API access to at least your CheckMK server IP address.
+ Shows several information about a Mailcow mailbox, e.g. number of messages and quota.
+ The check will raise WARN/CRIT if quota usage is above the configurable levels.
+ The check will raise WARN/CRIT if number of messages is above the configurable levels. 
+item:
+ mailboxname
+inventory:
+ one service is created for each mailbox
\ No newline at end of file
diff --git a/local/share/check_mk/web/plugins/metrics/mailcow_metrics.py b/local/share/check_mk/web/plugins/metrics/mailcow_metrics.py
index 8e37082..5e87acf 100644
--- a/local/share/check_mk/web/plugins/metrics/mailcow_metrics.py
+++ b/local/share/check_mk/web/plugins/metrics/mailcow_metrics.py
@@ -57,4 +57,16 @@ metric_info["mailcow_domains_configured_mailboxes"] = {
     "title": _("Number of Configured Mailboxes"),
     "unit": "count",
     "color": "24/b",
+}
+
+metric_info["mailcow_mailboxes_used_quota"] = {
+    "title": _("Mailbox Quota Used"),
+    "unit": "%",
+    "color": "24/a",
+}
+
+metric_info["mailcow_mailboxes_messages"] = {
+    "title": _("Number of Messages"),
+    "unit": "count",
+    "color": "24/b",
 }
\ No newline at end of file
diff --git a/local/share/check_mk/web/plugins/perfometer/mailcow_perfometers.py b/local/share/check_mk/web/plugins/perfometer/mailcow_perfometers.py
index 9a08574..b7bfea5 100644
--- a/local/share/check_mk/web/plugins/perfometer/mailcow_perfometers.py
+++ b/local/share/check_mk/web/plugins/perfometer/mailcow_perfometers.py
@@ -22,6 +22,17 @@ perfometer_info.append({
     ],
 })
 
+perfometer_info.append({
+    "type": "stacked",
+    "perfometers": [
+        {
+            "type": "linear",
+            "segments": ["mailcow_mailboxes_used_quota"],
+            "total": 100.0,
+        },
+    ],
+})
+
 #perfometer_info.append({
 #    "type": "stacked",
 #    "perfometers": [
diff --git a/local/share/check_mk/web/plugins/wato/mailcow_mailboxes_rules.py b/local/share/check_mk/web/plugins/wato/mailcow_mailboxes_rules.py
new file mode 100644
index 0000000..9ea4a38
--- /dev/null
+++ b/local/share/check_mk/web/plugins/wato/mailcow_mailboxes_rules.py
@@ -0,0 +1,63 @@
+from cmk.gui.i18n import _
+from cmk.gui.plugins.wato import (
+    CheckParameterRulespecWithItem,
+    rulespec_registry,
+    RulespecGroupCheckParametersApplications
+)
+from cmk.gui.valuespec import (
+    Dictionary,
+    ListChoice,
+    TextAscii,
+    Percentage,
+    Tuple,
+    Float,
+    Integer
+)    
+
+def _item_spec_mailcow_mailboxes():
+    return TextAscii(
+        title=_("Domain")
+    )
+
+def _parameter_spec_mailcow_mailboxes():
+    return Dictionary(
+        elements=[
+            ("levels_mailcow_mailboxes_quota_used", Tuple(
+                title=_("Mailcow mailbox quota usage for storage"),
+                    elements=[
+                        Percentage(
+                            title=_("Warning at"),
+                            default_value=65.0,
+                        ),
+                        Percentage(
+                            title=_("Critical at"),
+                            default_value=85.0,
+                        )
+                    ],
+            )),
+            ("levels_mailcow_mailboxes_num_messages", Tuple(
+                title=_("Number of messages in mailbox"),
+                    elements=[
+                        Integer(
+                            title=_("Warning at"),
+                            default_value=1000,
+                        ),
+                        Integer(
+                            title=_("Critical at"),
+                            default_value=2500,
+                        )
+                    ],
+            )),
+        ],
+    )
+
+rulespec_registry.register(
+    CheckParameterRulespecWithItem(
+        check_group_name="mailcow_mailboxes",
+        group=RulespecGroupCheckParametersApplications,
+        match_type="dict",
+        item_spec=_item_spec_mailcow_mailboxes,
+        parameter_valuespec=_parameter_spec_mailcow_mailboxes,
+        title=lambda: _("Levels for Mailcow mailboxes"),
+    )
+)
\ No newline at end of file
diff --git a/mkp/Mailcow-0.9.9.mkp b/mkp/Mailcow-0.9.9.mkp
new file mode 100755
index 0000000..980f12c
Binary files /dev/null and b/mkp/Mailcow-0.9.9.mkp differ