diff --git a/rpcs3/Emu/Cell/SPUThread.h b/rpcs3/Emu/Cell/SPUThread.h
index 0ab76b025c..bf2b0d4a6a 100644
--- a/rpcs3/Emu/Cell/SPUThread.h
+++ b/rpcs3/Emu/Cell/SPUThread.h
@@ -636,7 +636,7 @@ public:
 
 	static const u32 id_base = 0x02000000; // TODO (used to determine thread type)
 	static const u32 id_step = 1;
-	static const u32 id_count = (0xF0000000 - SPU_FAKE_BASE_ADDR) / SPU_LS_SIZE;
+	static const u32 id_count = (0xFFFC0000 - SPU_FAKE_BASE_ADDR) / SPU_LS_SIZE;
 
 	spu_thread(lv2_spu_group* group, u32 index, std::string_view name, u32 lv2_id, bool is_isolated = false, u32 option = 0);
 
diff --git a/rpcs3/Emu/Cell/lv2/sys_spu.h b/rpcs3/Emu/Cell/lv2/sys_spu.h
index 389608df25..1e48d986fe 100644
--- a/rpcs3/Emu/Cell/lv2/sys_spu.h
+++ b/rpcs3/Emu/Cell/lv2/sys_spu.h
@@ -262,6 +262,8 @@ struct lv2_spu_group
 	static const u32 id_count = 255;
 	static constexpr std::pair<u32, u32> id_invl_range = {0, 8};
 
+	static_assert(spu_thread::id_count == id_count * 6 + 5);
+
 	const std::string name;
 	const u32 id;
 	const u32 max_num;