diff --git a/lib/elixir/src/elixir_bitstring.erl b/lib/elixir/src/elixir_bitstring.erl
index f35fe56eba..00d72fda74 100644
--- a/lib/elixir/src/elixir_bitstring.erl
+++ b/lib/elixir/src/elixir_bitstring.erl
@@ -56,6 +56,11 @@ expr_type(_) -> default.
 %% Expands the expression of a bitstring, that is, the LHS of :: or
 %% an argument of the bitstring (such as "foo" in "<<foo>>").
 
+expand_expr(Meta, {{'.', M1, ['Elixir.Kernel', to_string]}, M2, [Arg]}, Fun, E) ->
+  case expand_expr(Meta, Arg, Fun, E) of
+    {Bin, _} = Pair when is_binary(Bin) -> Pair;
+    {EArg, EE} -> {{{'.', M1, ['Elixir.Kernel', to_string]}, M2, [EArg]}, EE}
+  end;
 expand_expr(Meta, Component, Fun, E) ->
   case Fun(Component, E) of
     {EComponent, _} when is_list(EComponent); is_atom(EComponent) ->
diff --git a/lib/elixir/test/elixir/kernel/expansion_test.exs b/lib/elixir/test/elixir/kernel/expansion_test.exs
index f05a0edf7e..156e3d2652 100644
--- a/lib/elixir/test/elixir/kernel/expansion_test.exs
+++ b/lib/elixir/test/elixir/kernel/expansion_test.exs
@@ -2,6 +2,7 @@ Code.require_file "../test_helper.exs", __DIR__
 
 defmodule Kernel.ExpansionTarget do
   defmacro seventeen, do: 17
+  defmacro bar, do: "bar"
 end
 
 defmodule Kernel.ExpansionTest do
@@ -980,6 +981,12 @@ defmodule Kernel.ExpansionTest do
   end
 
   describe "bitstrings" do
+    test "inlines binaries inside interpolation" do
+      import Kernel.ExpansionTarget
+      assert expand(quote do: "foo#{bar()}" = "foobar") ==
+             quote do: (<<"foo"::binary(), "bar"::binary()>> = "foobar")
+    end
+
     test "expands size * unit" do
       import Kernel, except: [-: 2]
 
@@ -1045,13 +1052,13 @@ defmodule Kernel.ExpansionTest do
 
     test "expands macro specifiers" do
       import Kernel, except: [-: 2]
+      import Kernel.ExpansionTarget
 
-      assert expand(quote do: (import Kernel.ExpansionTarget; <<x::seventeen>>)) ==
-             quote do: (:"Elixir.Kernel.ExpansionTarget"; <<x()::integer()-size(17)>>)
+      assert expand(quote do: <<x::seventeen>>) ==
+             quote do: (<<x()::integer()-size(17)>>)
 
-      assert expand(quote do: (import Kernel.ExpansionTarget; <<seventeen::seventeen, x::size(seventeen)>> = 1)) ==
-             quote do: (:"Elixir.Kernel.ExpansionTarget";
-                        <<seventeen::integer()-size(17), x::integer()-size(seventeen)>> = 1)
+      assert expand(quote do: (<<seventeen::seventeen, x::size(seventeen)>> = 1)) ==
+             quote do: (<<seventeen::integer()-size(17), x::integer()-size(seventeen)>> = 1)
     end
 
     test "expands macro in args" do