diff --git a/doc/languages-frameworks/python.section.md b/doc/languages-frameworks/python.section.md
index fe02344a72cd..86633c827dfd 100644
--- a/doc/languages-frameworks/python.section.md
+++ b/doc/languages-frameworks/python.section.md
@@ -484,9 +484,9 @@ and in this case the `python35` interpreter is automatically used.
 ### Interpreters
 
 Versions 2.7, 3.4, 3.5, 3.6 and 3.7 of the CPython interpreter are available as
-respectively `python27`, `python34`, `python35` and `python36`. The PyPy interpreter
+respectively `python27`, `python34`, `python35`, `python36` and `python37`. The PyPy interpreter
 is available as `pypy`. The aliases `python2` and `python3` correspond to respectively `python27` and
-`python35`. The default interpreter, `python`, maps to `python2`.
+`python37`. The default interpreter, `python`, maps to `python2`.
 The Nix expressions for the interpreters can be found in
 `pkgs/development/interpreters/python`.
 
@@ -538,7 +538,7 @@ sets are
 and the aliases
 
 * `pkgs.python2Packages` pointing to `pkgs.python27Packages`
-* `pkgs.python3Packages` pointing to `pkgs.python36Packages`
+* `pkgs.python3Packages` pointing to `pkgs.python37Packages`
 * `pkgs.pythonPackages` pointing to `pkgs.python2Packages`
 
 #### `buildPythonPackage` function
diff --git a/nixos/doc/manual/release-notes/rl-1903.xml b/nixos/doc/manual/release-notes/rl-1903.xml
index 839d75b53bd1..77f58b224d7f 100644
--- a/nixos/doc/manual/release-notes/rl-1903.xml
+++ b/nixos/doc/manual/release-notes/rl-1903.xml
@@ -19,6 +19,8 @@
 
   <itemizedlist>
    <listitem>
+    <para>
+    The default Python 3 interpreter is now CPython 3.7 instead of CPython 3.6.
     <para />
    </listitem>
   </itemizedlist>
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 45984c3e9678..82f8f8672810 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -7756,7 +7756,7 @@ with pkgs;
   # When switching these sets, please update docs at ../../doc/languages-frameworks/python.md
   python = python2;
   python2 = python27;
-  python3 = python36;
+  python3 = python37;
   pypy = pypy27;
 
   # Python interpreter that is build with all modules, including tkinter.
@@ -7806,8 +7806,8 @@ with pkgs;
   python27Packages = lib.hiPrioSet (recurseIntoAttrs python27.pkgs);
   python34Packages = python34.pkgs;
   python35Packages = python35.pkgs;
-  python36Packages = recurseIntoAttrs python36.pkgs;
-  python37Packages = python37.pkgs;
+  python36Packages = python36.pkgs;
+  python37Packages = recurseIntoAttrs python37.pkgs;
   pypyPackages = pypy.pkgs;
 
   # Should eventually be moved inside Python interpreters.