diff --git a/src/fastcs/transports/epics/ca/util.py b/src/fastcs/transports/epics/ca/util.py
index 6a3e6dd8..66803951 100644
--- a/src/fastcs/transports/epics/ca/util.py
+++ b/src/fastcs/transports/epics/ca/util.py
@@ -13,13 +13,13 @@
 from fastcs.exceptions import FastCSError
 from fastcs.transports.epics.util import validate_epics_pv_id
 
-_CA_ID_RE = re.compile(r"^[A-Za-z0-9_-]+$")
+_CA_ID_RE = re.compile(r"^[A-Za-z0-9_:-]+$")
 
 
 def validate_ca_id(controller_api: ControllerAPI) -> None:
     """Reject controller ids that wouldn't be safe in an EPICS CA PV name.
 
-    Rejects ids with characters outside ``[A-Za-z0-9_-]`` and rejects setups
+    Rejects ids with characters outside ``[A-Za-z0-9_:-]`` and rejects setups
     where the longest derivable PV prefix already exceeds the 60-character
     EPICS PV name limit.
     """
diff --git a/src/fastcs/transports/epics/pva/util.py b/src/fastcs/transports/epics/pva/util.py
index 624e378f..0722a023 100644
--- a/src/fastcs/transports/epics/pva/util.py
+++ b/src/fastcs/transports/epics/pva/util.py
@@ -3,13 +3,13 @@
 from fastcs.controllers import ControllerAPI
 from fastcs.transports.epics.util import validate_epics_pv_id
 
-_PVA_ID_RE = re.compile(r"^[A-Za-z0-9_-]+$")
+_PVA_ID_RE = re.compile(r"^[A-Za-z0-9_:-]+$")
 
 
 def validate_pva_id(controller_api: ControllerAPI) -> None:
     """Reject controller ids that wouldn't be safe in an EPICS PVA PV name.
 
-    Rejects ids with characters outside ``[A-Za-z0-9_-]`` and rejects setups
+    Rejects ids with characters outside ``[A-Za-z0-9_:-]`` and rejects setups
     where the longest derivable PV prefix already exceeds the 60-character
     EPICS PV name limit.
     """
diff --git a/src/fastcs/transports/epics/util.py b/src/fastcs/transports/epics/util.py
index d591d1ef..6e81faba 100644
--- a/src/fastcs/transports/epics/util.py
+++ b/src/fastcs/transports/epics/util.py
@@ -36,7 +36,7 @@ def validate_epics_pv_id(
     if not id_re.fullmatch(name):
         raise ValueError(
             f"Controller id {name!r} is not a valid {transport_label}; "
-            "only alphanumerics, '-' and '_' are allowed"
+            "only alphanumerics, '-', '_', and ':' are allowed"
         )
     longest_prefix = max(
         len(pv_prefix_from_path(api.path)) for api in controller_api.walk_api()
diff --git a/tests/transports/epics/ca/test_ca_util.py b/tests/transports/epics/ca/test_ca_util.py
index 463a17dc..fd59dc35 100644
--- a/tests/transports/epics/ca/test_ca_util.py
+++ b/tests/transports/epics/ca/test_ca_util.py
@@ -140,7 +140,7 @@ def test_validate_ca_id_accepts_valid(id):
     validate_ca_id(ControllerAPI(path=[id]))
 
 
-@pytest.mark.parametrize("id", ["bad/id", "with space", "colons:in:id", ""])
+@pytest.mark.parametrize("id", ["bad/id", "with space", ""])
 def test_validate_ca_id_rejects_illegal_characters(id):
     with pytest.raises(ValueError, match="EPICS CA id"):
         validate_ca_id(ControllerAPI(path=[id]))
diff --git a/tests/transports/epics/pva/test_pva_util.py b/tests/transports/epics/pva/test_pva_util.py
index 13cd5bb8..5f895042 100644
--- a/tests/transports/epics/pva/test_pva_util.py
+++ b/tests/transports/epics/pva/test_pva_util.py
@@ -9,7 +9,7 @@ def test_validate_pva_id_accepts_valid(name):
     validate_pva_id(ControllerAPI(path=[name]))
 
 
-@pytest.mark.parametrize("name", ["bad/id", "with space", "colons:in:id", ""])
+@pytest.mark.parametrize("name", ["bad/id", "with space", ""])
 def test_validate_pva_id_rejects_illegal_characters(name):
     with pytest.raises(ValueError, match="EPICS PVA id"):
         validate_pva_id(ControllerAPI(path=[name]))