diff --git a/toolchain/sem_ir/file.cpp b/toolchain/sem_ir/file.cpp
index 69b7e13db9af..53f0a710a09b 100644
--- a/toolchain/sem_ir/file.cpp
+++ b/toolchain/sem_ir/file.cpp
@@ -40,12 +40,12 @@ File::File(const Parse::Tree* parse_tree, CheckIRId check_ir_id,
       classes_(check_ir_id),
       associated_constants_(check_ir_id),
       impls_(*this),
-      specific_interfaces_(check_ir_id_),
+      specific_interfaces_(check_ir_id),
       // The `+1` prevents adding a tag to the global `NameSpace::PackageInstId`
       // instruction. It's not a "singleton" instruction, but it's a unique
       // instruction id that comes right after the singletons.
       insts_(this, SingletonInstKinds.size() + 1),
-      vtables_(IdTag(check_ir_id.index, 0)),
+      vtables_(check_ir_id),
       constant_values_(ConstantId::NotConstant, &insts_),
       inst_blocks_(allocator_),
       constants_(this) {