diff --git a/cylc/flow/rundb.py b/cylc/flow/rundb.py
index 558646c96d7..6fd6882cc3a 100644
--- a/cylc/flow/rundb.py
+++ b/cylc/flow/rundb.py
@@ -21,6 +21,7 @@
 
 from cylc.flow import LOG
 import cylc.flow.flags
+from cylc.flow.task_state import TASK_STATUS_WAITING
 from cylc.flow.wallclock import get_current_time_string
 
 
@@ -881,6 +882,58 @@ def remove_columns(self, table, to_drop):
         # done
         conn.commit()
 
+    def upgrade_retry_state(self):
+        """Replace the retry state with xtriggers.
+
+        * Change *retring tasks to waiting
+        * Add the required xtrigger
+
+        Note:
+            The retry status can be safely removed as this is really a display
+            state, the retry logic revolves around the TaskActionTimer.
+
+        From:
+            cylc<8
+        To:
+            cylc>=8
+        PR:
+            #3423
+
+        Returns:
+            list - (cycle, name, status) tuples of all retrying tasks.
+
+        """
+        conn = self.connect()
+
+        for table in [self.TABLE_TASK_POOL_CHECKPOINTS, self.TABLE_TASK_POOL]:
+            tasks = list(conn.execute(
+                rf'''
+                    SELECT
+                        cycle, name, status
+                    FROM
+                        {table}
+                    WHERE
+                        status IN ('retrying', 'submit-retrying')
+                '''
+            ))
+            if tasks:
+                LOG.info(f'Upgrade retrying tasks in table {table}')
+            conn.executemany(
+                rf'''
+                    UPDATE
+                        {table}
+                    SET
+                        status='{TASK_STATUS_WAITING}'
+                    WHERE
+                        cycle==?
+                        and name==?
+                        and status==?
+                ''',
+                tasks
+            )
+        conn.commit()
+        return tasks
+
     def upgrade_is_held(self):
         """Upgrade hold_swap => is_held.
 
diff --git a/cylc/flow/suite_db_mgr.py b/cylc/flow/suite_db_mgr.py
index 59209a7304e..649657aad2d 100644
--- a/cylc/flow/suite_db_mgr.py
+++ b/cylc/flow/suite_db_mgr.py
@@ -520,6 +520,9 @@ def restart_upgrade(self):
         """Vacuum/upgrade runtime DB on restart."""
         pri_dao = self.get_pri_dao()
         pri_dao.vacuum()
+
         # compat: <8.0
         pri_dao.upgrade_is_held()
+        pri_dao.upgrade_retry_state()
+
         pri_dao.close()
diff --git a/cylc/flow/task_action_timer.py b/cylc/flow/task_action_timer.py
index 6fe44f5e842..e8f37527c93 100644
--- a/cylc/flow/task_action_timer.py
+++ b/cylc/flow/task_action_timer.py
@@ -24,8 +24,8 @@
 
 class TimerFlags:
 
-    EXECUTION_RETRY = 'EXECUTION_RETRY'
-    SUBMISSION_RETRY = 'SUBMISSION_RETRY'
+    EXECUTION_RETRY = 'execution-retry'
+    SUBMISSION_RETRY = 'submission-retry'
 
 
 class TaskActionTimer(object):
diff --git a/cylc/flow/task_events_mgr.py b/cylc/flow/task_events_mgr.py
index 78cb29a8f00..a562aef2540 100644
--- a/cylc/flow/task_events_mgr.py
+++ b/cylc/flow/task_events_mgr.py
@@ -686,7 +686,7 @@ def _job_logs_retrieval_callback(self, proc_ctx, schd_ctx):
             except KeyError as exc:
                 LOG.exception(exc)
 
-    def _retry_task(self, itask, timer, submit_retry=False):
+    def _retry_task(self, itask, wallclock_time, submit_retry=False):
         """Retry a task.
 
         Args:
@@ -706,7 +706,7 @@ def _retry_task(self, itask, timer, submit_retry=False):
             itask.identity
         ))
         kwargs = {
-            'absolute_as_seconds': timer.timeout
+            'absolute_as_seconds': wallclock_time
         }
 
         # if this isn't the first retry the xtrigger will already exist
@@ -731,23 +731,6 @@ def _retry_task(self, itask, timer, submit_retry=False):
             itask.state.add_xtrigger(label)
         itask.state.reset(TASK_STATUS_WAITING)
 
-
-    def _get_retry_xtrigger(self, itask, unix_time, submit_retry=False):
-        label = (
-            'cylc',
-            'submit_retry' if submit_retry else 'retry',
-            itask.identity
-        ).join('_')
-        xtrig = SubFuncContext(
-            label,
-            'wall_clock',
-            [],
-            {
-                'absolute_as_seconds': unix_time
-            }
-        )
-        return label, xtrig
-
     def _process_message_failed(self, itask, event_time, message):
         """Helper for process_message, handle a failed message."""
         if event_time is None:
@@ -773,7 +756,7 @@ def _process_message_failed(self, itask, event_time, message):
         else:
             # There is an execution retry lined up.
             timer = itask.try_timers[TimerFlags.EXECUTION_RETRY]
-            self._retry_task(itask, timer)
+            self._retry_task(itask, timer.timeout)
             delay_msg = f"retrying in {timer.delay_timeout_as_str()}"
             if itask.state.is_held:
                 delay_msg = "held (%s)" % delay_msg
@@ -862,7 +845,7 @@ def _process_message_submit_failed(self, itask, event_time):
         else:
             # There is a submission retry lined up.
             timer = itask.try_timers[TimerFlags.SUBMISSION_RETRY]
-            self._retry_task(itask, timer, submit_retry=True)
+            self._retry_task(itask, timer.timeout, submit_retry=True)
             delay_msg = f"submit-retrying in {timer.delay_timeout_as_str()}"
             if itask.state.is_held:
                 delay_msg = "held (%s)" % delay_msg
diff --git a/cylc/flow/task_pool.py b/cylc/flow/task_pool.py
index 909fe241d23..f4e5186b417 100644
--- a/cylc/flow/task_pool.py
+++ b/cylc/flow/task_pool.py
@@ -38,7 +38,7 @@
 from cylc.flow.cycling.loader import get_point, standardise_point_string
 from cylc.flow.exceptions import SuiteConfigError, PointParsingError
 from cylc.flow.suite_status import StopMode
-from cylc.flow.task_action_timer import TaskActionTimer
+from cylc.flow.task_action_timer import TaskActionTimer, TimerFlags
 from cylc.flow.task_events_mgr import (
     CustomTaskEventHandlerContext, TaskEventMailContext,
     TaskJobLogsRetrieveContext)
@@ -456,6 +456,7 @@ def load_db_task_action_timers(self, row_idx, row):
                 "%(id)s: skip action timer %(ctx_key)s" %
                 {"id": id_, "ctx_key": ctx_key_raw})
             return
+        LOG.info("+ %s.%s %s" % (name, cycle, ctx_key))
         if ctx_key == "poll_timer" or ctx_key[0] == "poll_timers":
             # "poll_timers" for back compat with <=7.6.X
             itask = self.get_task_by_id(id_)
@@ -469,6 +470,22 @@ def load_db_task_action_timers(self, row_idx, row):
             if itask is None:
                 LOG.warning("%(id)s: task not found, skip" % {"id": id_})
                 return
+            if 'retrying' in ctx_key[1]:
+                if 'submit' in ctx_key[1]:
+                    submit = True
+                    ctx_key[1] = TimerFlags.SUBMISSION_RETRY
+                else:
+                    submit = False
+                    ctx_key[1] = TimerFlags.EXECUTION_RETRY
+
+                if timeout:
+                    LOG.info(
+                        f'  (upgrading retrying state for {itask.identity})')
+                    self.task_events_mgr._retry_task(
+                        itask,
+                        float(timeout),
+                        submit_retry=submit
+                    )
             itask.try_timers[ctx_key[1]] = TaskActionTimer(
                 ctx, delays, num, delay, timeout)
         elif ctx:
@@ -485,7 +502,6 @@ def load_db_task_action_timers(self, row_idx, row):
                 "%(id)s: skip action timer %(ctx_key)s" %
                 {"id": id_, "ctx_key": ctx_key_raw})
             return
-        LOG.info("+ %s.%s %s" % (name, cycle, ctx_key))
 
     def release_runahead_task(self, itask):
         """Release itask to the appropriate queue in the active pool."""
diff --git a/cylc/flow/tests/test_rundb.py b/cylc/flow/tests/test_rundb.py
index 694daf134ee..31edcd87c13 100644
--- a/cylc/flow/tests/test_rundb.py
+++ b/cylc/flow/tests/test_rundb.py
@@ -101,9 +101,75 @@ def test_remove_columns():
         assert data == [('PUB',)]
 
 
+def test_upgrade_retry_state():
+    """Pre Cylc8 DB upgrade compatibility test."""
+    initial_data = [
+        # (name, cycle, status)
+        ('foo', '1', 'waiting'),
+        ('bar', '1', 'running'),
+        ('baz', '1', 'retrying'),
+        ('pub', '1', 'submit-retrying')
+    ]
+    expected_data = [
+        # (name, cycle, status)
+        ('foo', '1', 'waiting'),
+        ('bar', '1', 'running'),
+        ('baz', '1', 'waiting'),
+        ('pub', '1', 'waiting')
+    ]
+    tables = [
+        CylcSuiteDAO.TABLE_TASK_POOL,
+        CylcSuiteDAO.TABLE_TASK_POOL_CHECKPOINTS
+    ]
+
+    with create_temp_db() as (temp_db, conn):
+        # initialise tables
+        for table in tables:
+            conn.execute(
+                rf'''
+                    CREATE TABLE {table} (
+                        name varchar(255),
+                        cycle varchar(255),
+                        status varchar(255)
+                    )
+                '''
+            )
+
+            conn.executemany(
+                rf'''
+                    INSERT INTO {table}
+                    VALUES (?,?,?)
+                ''',
+                initial_data
+            )
+
+        # close database
+        conn.commit()
+        conn.close()
+
+        # open database as cylc dao
+        dao = CylcSuiteDAO(temp_db)
+        conn = dao.connect()
+
+        # check the initial data was correctly inserted
+        for table in tables:
+            dump = [x for x in conn.execute(rf'SELECT * FROM {table}')]
+            assert dump == initial_data
+
+        # upgrade
+        assert dao.upgrade_retry_state() == [
+            ('1', 'baz', 'retrying'),
+            ('1', 'pub', 'submit-retrying')
+        ]
+
+        # check the data was correctly upgraded
+        for table in tables:
+            dump = [x for x in conn.execute(rf'SELECT * FROM task_pool')]
+            assert dump == expected_data
+
+
 def test_upgrade_hold_swap():
     """Pre Cylc8 DB upgrade compatibility test."""
-    # test data
     initial_data = [
         # (name, cycle, status, hold_swap)
         ('foo', '1', 'waiting', ''),
diff --git a/tests/retries/02-xtriggers/reference.log b/tests/retries/02-xtriggers/reference.log
new file mode 100644
index 00000000000..671654b8090
--- /dev/null
+++ b/tests/retries/02-xtriggers/reference.log
@@ -0,0 +1,8 @@
+Initial point: 1
+Final point: 1
+[retry.1] -triggered off []
+[retry.1] -triggered off []
+[retry.1] -triggered off []
+[retry.1] -triggered off []
+[retry.1] -triggered off []
+[test.1] -triggered off ['retry.1']
diff --git a/tests/retries/03-upgrade.t b/tests/retries/03-upgrade.t
new file mode 100644
index 00000000000..847487270bf
--- /dev/null
+++ b/tests/retries/03-upgrade.t
@@ -0,0 +1,42 @@
+#!/bin/bash
+# THIS FILE IS PART OF THE CYLC SUITE ENGINE.
+# Copyright (C) 2008-2019 NIWA & British Crown (Met Office) & Contributors.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#-------------------------------------------------------------------------------
+# Compat: Cylc<8
+# Test the upgrade of the old *retrying states to the new xtrigger based
+# retry mechanism.
+. "$(dirname "$0")/test_header"
+set_test_number 7
+install_suite
+
+# install the cylc7 restart database
+cp "${TEST_SOURCE_DIR}/${TEST_NAME_BASE}/.service/db" \
+    "${HOME}/cylc-run/${SUITE_NAME}/.service/db"
+
+run_ok "${TEST_NAME_BASE}-run" cylc restart "${SUITE_NAME}"
+
+FILE="$(cylc cat-log "${SUITE_NAME}" -m p)"
+log_scan "${TEST_NAME_BASE}-retries" "${FILE}" 30 0.5 \
+    '(upgrading retrying state for b.1)' \
+    'xtrigger satisfied: cylc_retry_b.1' \
+    '\[b.1\] -submit-num=02' \
+    '\[b.1\] status=running: (received)failed/EXIT.*job(02)' \
+    '\[b.1\] -job(02) failed, retrying in PT2S' \
+    'xtrigger satisfied: cylc_retry_b.1'
+
+poll_suite_stopped
+
+exit
diff --git a/tests/retries/03-upgrade/.service/db b/tests/retries/03-upgrade/.service/db
new file mode 100644
index 00000000000..3a923a576e6
Binary files /dev/null and b/tests/retries/03-upgrade/.service/db differ
diff --git a/tests/retries/03-upgrade/suite.rc b/tests/retries/03-upgrade/suite.rc
new file mode 100644
index 00000000000..3da90c2b7d9
--- /dev/null
+++ b/tests/retries/03-upgrade/suite.rc
@@ -0,0 +1,19 @@
+[cylc]
+    [[events]]
+        abort on inactivity = True
+        abort on timeout = True
+        inactivity = PT1M
+        timeout = PT1M
+
+[scheduling]
+    [[dependencies]]
+        graph = """
+            a => b => c
+        """
+
+[runtime]
+    [[b]]
+        # fail four times then pass
+        script = test "$CYLC_TASK_SUBMIT_NUMBER" -ge 5;
+        [[[job]]]
+            execution retry delays = 3*PT2S