diff --git a/README.md b/README.md
index 98eb9360..40e20b0f 100644
--- a/README.md
+++ b/README.md
@@ -64,6 +64,8 @@ Options:
   do not reboot after installation, allowing further customization of the target installation.
 * --kexec url
   use another kexec tarball to bootstrap NixOS
+* --skip-reformat
+  dont format disks with disko (only mount)
 * --stop-after-disko
   exit after disko formating, you can then proceed to install manually or some other way
 * --extra-files files
diff --git a/src/nixos-anywhere.sh b/src/nixos-anywhere.sh
index a3a7f967..48a129b4 100755
--- a/src/nixos-anywhere.sh
+++ b/src/nixos-anywhere.sh
@@ -15,6 +15,8 @@ Options:
   do not reboot after installation, allowing further customization of the target installation.
 * --kexec url
   use another kexec tarball to bootstrap NixOS
+* --skip-reformat
+  dont format disks with disko (only mount)
 * --stop-after-disko
   exit after disko formating, you can then proceed to install manually or some other way
 * --extra-files files
@@ -89,6 +91,9 @@ while [[ $# -gt 0 ]]; do
     shift
     shift
     ;;
+  --skip-reformat)
+    skip_reformat=y
+    ;;
   --stop-after-disko)
     stop_after_disko=y
     ;;
@@ -294,7 +299,12 @@ for path in "${!disk_encryption_keys[@]}"; do
 done
 
 nix_copy --to "ssh://$ssh_connection" "$disko_script"
-ssh_ "$disko_script"
+if [[ ${skip_reformat} == "y" ]]; then
+  echo "Skipping disko partitioning (only do mount)."
+  ssh_ "$disko_script -m mount"
+else
+  ssh_ "$disko_script"
+fi
 
 if [[ ${stop_after_disko-n} == "y" ]]; then
   # Should we also do this for `--no-reboot`?