diff --git a/CHANGELOG.md b/CHANGELOG.md
index 10b6933b27..a24a6db506 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
 # Changelog
 
+## v1.6.4 - 2021-06-23
+
+[full changelog](https://github.com/aiidateam/aiida-core/compare/v1.6.3...v1.6.4)
+
+This is a patch release to pin `psycopg2-binary` to version 2.8.x, to avoid an issue with database creation in version 2.9 ([#4989](https://github.com/aiidateam/aiida-core/pull/4989)).
+
 ## v1.6.3 - 2021-04-28
 
 [full changelog](https://github.com/aiidateam/aiida-core/compare/v1.6.2...v1.6.3) | [GitHub contributors page for this release](https://github.com/aiidateam/aiida-core/graphs/contributors?from=2021-04-281&to=2021-04-28&type=c)
diff --git a/aiida/__init__.py b/aiida/__init__.py
index e413f46003..8813a864d5 100644
--- a/aiida/__init__.py
+++ b/aiida/__init__.py
@@ -31,7 +31,7 @@
     'For further information please visit http://www.aiida.net/. All rights reserved.'
 )
 __license__ = 'MIT license, see LICENSE.txt file.'
-__version__ = '1.6.3'
+__version__ = '1.6.4'
 __authors__ = 'The AiiDA team.'
 __paper__ = (
     'S. P. Huber et al., "AiiDA 1.0, a scalable computational infrastructure for automated reproducible workflows and '
diff --git a/environment.yml b/environment.yml
index 8f0b29eabf..849c4a23fb 100644
--- a/environment.yml
+++ b/environment.yml
@@ -28,7 +28,7 @@ dependencies:
 - plumpy~=0.19.0
 - pgsu~=0.2.0
 - psutil~=5.6
-- psycopg2>=2.8.3,~=2.8
+- psycopg2-binary~=2.8.3
 - python-dateutil~=2.8
 - pytz~=2019.3
 - pyyaml~=5.1.2
diff --git a/setup.json b/setup.json
index 94f120eecd..a37a793718 100644
--- a/setup.json
+++ b/setup.json
@@ -1,6 +1,6 @@
 {
     "name": "aiida-core",
-    "version": "1.6.3",
+    "version": "1.6.4",
     "url": "http://www.aiida.net/",
     "license": "MIT License",
     "author": "The AiiDA team",
@@ -42,7 +42,7 @@
         "plumpy~=0.19.0",
         "pgsu~=0.2.0",
         "psutil~=5.6",
-        "psycopg2-binary~=2.8,>=2.8.3",
+        "psycopg2-binary~=2.8.3",
         "python-dateutil~=2.8",
         "pytz~=2019.3",
         "pyyaml~=5.1.2",
diff --git a/utils/dependency_management.py b/utils/dependency_management.py
index cc4848966a..33e96c74b7 100755
--- a/utils/dependency_management.py
+++ b/utils/dependency_management.py
@@ -26,7 +26,6 @@
 ROOT = Path(__file__).resolve().parent.parent  # repository root
 
 SETUPTOOLS_CONDA_MAPPINGS = {
-    'psycopg2-binary': 'psycopg2',
     'graphviz': 'python-graphviz',
 }