diff --git a/docs/source/download.rst b/docs/source/download.rst
index fc1c11f9d9..4b9a2cfbd0 100644
--- a/docs/source/download.rst
+++ b/docs/source/download.rst
@@ -107,7 +107,7 @@ packages can be installed into an existing Firedrake installation using
 System requirements
 -------------------
 
-Firedrake requires Python 3.9 to 3.13. The installation script is
+Firedrake requires Python 3.10 to 3.13. The installation script is
 tested by CI on Ubuntu 24.04 LTS. On Ubuntu 22.04 or later, the system
 installed Python 3 is supported. On MacOS, the homebrew_ installed
 Python 3 is supported::
@@ -126,7 +126,7 @@ they have the system dependencies:
 * A Fortran compiler (for PETSc)
 * Blas and Lapack
 * Git, Mercurial
-* Python version 3.9-3.13
+* Python version 3.10-3.13
 * The Python headers
 * autoconf, automake, libtool
 * CMake
diff --git a/docs/source/install-debug.dot b/docs/source/install-debug.dot
index ec324c6c78..c11f85ef4c 100644
--- a/docs/source/install-debug.dot
+++ b/docs/source/install-debug.dot
@@ -8,7 +8,7 @@ digraph triage {
     venv_activated [label="venv activated?"];
     install_script_up_to_date [label="Install script\nup to date?"];
     using_anaconda [label="Using\nAnaconda?"];
-    python_version [label="Python <3.9?"];
+    python_version [label="Python <3.10?"];
     using_macos [label="Using\nMacOS?"];
     using_homebrew [label="Using\nHomebrew?"];
     url_error [label="URL Error with SSL\ncertificate failure?"];
@@ -16,7 +16,7 @@ digraph triage {
 
     activate_venv [label="Activate the\nvenv first."];
     uninstall_anaconda [label="Deactivate\nAnaconda."];
-    update_python [label="Get Python 3.9-3.13"];
+    update_python [label="Get Python 3.10-3.13"];
     update_install_script [label="Fetch new\ninstall script"];
     get_homebrew [label="Use Homebrew."];
     brew_doctor [label="brew doctor"];
diff --git a/scripts/firedrake-install b/scripts/firedrake-install
index c167f75ffc..f9ded603f0 100755
--- a/scripts/firedrake-install
+++ b/scripts/firedrake-install
@@ -135,11 +135,11 @@ log.info("Running %s" % " ".join(sys.argv))
 if sys.version_info >= (3, 14):
     print("""\nCan not install Firedrake with Python 3.14 at the moment:
 Some wheels are not yet available for Python 3.14 for some required package(s).
-Please install with Python 3.13 (or an earlier version >= 3.9).""")
+Please install with Python 3.13 (or an earlier version >= 3.10).""")
     sys.exit(1)
-elif sys.version_info < (3, 9):
+elif sys.version_info < (3, 10):
     if mode == "install":
-        print("""\nInstalling Firedrake requires Python 3, at least version 3.9.
+        print("""\nInstalling Firedrake requires Python 3, at least version 3.10.
 You should run firedrake-install with python3.""")
     if mode == "update":
         if hasattr(sys, "real_prefix"):