diff --git a/CHANGES b/CHANGES
index 5fb6b4d01..4255015f2 100644
--- a/CHANGES
+++ b/CHANGES
@@ -15,6 +15,7 @@ Other fixes:
  - All: Correct more format strings on Windows (fixes mgba.io/i/1817)
  - CMake: Fix build with libzip 1.7
  - GB Core: Fix extracting SRAM when none is present
+ - GBA: Fix leak if attempting to load BIOS multiple times
  - GBA Savedata: Fix extracting save when not yet configured in-game
  - Qt: Fix file handle leak on opening an invalid ROM
  - Qt: Fix Italian RTC translation (fixes mgba.io/i/1798)
diff --git a/src/gba/gba.c b/src/gba/gba.c
index 43fe7cc26..d5608cdab 100644
--- a/src/gba/gba.c
+++ b/src/gba/gba.c
@@ -444,7 +444,6 @@ void GBAYankROM(struct GBA* gba) {
 }
 
 void GBALoadBIOS(struct GBA* gba, struct VFile* vf) {
-	gba->biosVf = vf;
 	if (vf->size(vf) != SIZE_BIOS) {
 		mLOG(GBA, WARN, "Incorrect BIOS size");
 		return;
@@ -454,6 +453,11 @@ void GBALoadBIOS(struct GBA* gba, struct VFile* vf) {
 		mLOG(GBA, WARN, "Couldn't map BIOS");
 		return;
 	}
+	if (gba->biosVf) {
+		gba->biosVf->unmap(gba->biosVf, gba->memory.bios, SIZE_BIOS);
+		gba->biosVf->close(gba->biosVf);
+	}
+	gba->biosVf = vf;
 	gba->memory.bios = bios;
 	gba->memory.fullBios = 1;
 	uint32_t checksum = GBAChecksum(gba->memory.bios, SIZE_BIOS);