diff --git a/.github/alternate_byond_versions.txt b/.github/alternate_byond_versions.txt
index 7b50af46885..111e573827e 100644
--- a/.github/alternate_byond_versions.txt
+++ b/.github/alternate_byond_versions.txt
@@ -5,3 +5,4 @@
 # Format is version: map
 # Example:
 # 500.1337: runtimestation
+515.1621: runtimestation
diff --git a/code/__byond_version_compat.dm b/code/__byond_version_compat.dm
index f3677cf2c64..5eb4bda14e7 100644
--- a/code/__byond_version_compat.dm
+++ b/code/__byond_version_compat.dm
@@ -2,11 +2,11 @@
 
 //Update this whenever you need to take advantage of more recent byond features
 #define MIN_COMPILER_VERSION 515
-#define MIN_COMPILER_BUILD 1609
+#define MIN_COMPILER_BUILD 1621
 #if (DM_VERSION < MIN_COMPILER_VERSION || DM_BUILD < MIN_COMPILER_BUILD) && !defined(SPACEMAN_DMM)
 //Don't forget to update this part
 #error Your version of BYOND is too out-of-date to compile this project. Go to https://secure.byond.com/download and update.
-#error You need version 515.1609 or higher
+#error You need version 515.1621 or higher
 #endif
 
 // Keep savefile compatibilty at minimum supported level