diff --git a/src/comp/syntax/ext/fmt.rs b/src/comp/syntax/ext/fmt.rs
index 121300f6490..30879dc8a0a 100644
--- a/src/comp/syntax/ext/fmt.rs
+++ b/src/comp/syntax/ext/fmt.rs
@@ -243,7 +243,6 @@ fn pieces_to_expr(cx: &ext_ctxt, sp: span, pieces: &[piece],
         }
         alt cnv.ty {
           ty_str. { ret make_conv_call(cx, arg.span, ~"str", cnv, arg); }
-          ty_istr. { ret make_conv_call(cx, arg.span, ~"istr", cnv, arg); }
           ty_int(sign) {
             alt sign {
               signed. { ret make_conv_call(cx, arg.span, ~"int", cnv, arg); }
@@ -300,7 +299,6 @@ fn pieces_to_expr(cx: &ext_ctxt, sp: span, pieces: &[piece],
         alt c.ty {
           ty_bool. { log "type: bool"; }
           ty_str. { log "type: str"; }
-          ty_istr. { log "type: istr"; }
           ty_char. { log "type: char"; }
           ty_int(s) {
             alt s {
diff --git a/src/lib/extfmt.rs b/src/lib/extfmt.rs
index 84c642d2883..c66ab2ad5e0 100644
--- a/src/lib/extfmt.rs
+++ b/src/lib/extfmt.rs
@@ -41,8 +41,6 @@ mod ct {
         ty_bits;
         ty_hex(caseness);
         ty_octal;
-        // FIXME: Transitional
-        ty_istr;
         // FIXME: More types
     }
     tag flag {
@@ -226,8 +224,6 @@ mod ct {
                 ty_bool
             } else if str::eq(tstr, "s") {
                 ty_str
-            } else if str::eq(tstr, "S") {
-                ty_istr
             } else if str::eq(tstr, "c") {
                 ty_char
             } else if str::eq(tstr, "d") || str::eq(tstr, "i") {
@@ -325,10 +321,6 @@ mod rt {
         ret pad(cv, unpadded, pad_nozero);
     }
 
-    fn conv_istr(cv: &conv, s: &istr) -> str {
-        ret conv_str(cv, istr::to_estr(s));
-    }
-
     // Convert an int to string with minimum number of digits. If precision is
     // 0 and num is 0 then the result is the empty string.
     fn int_to_str_prec(num: int, radix: uint, prec: uint) -> str {
diff --git a/src/test/run-pass/syntax-extension-fmt-istr.rs b/src/test/run-pass/syntax-extension-fmt-istr.rs
deleted file mode 100644
index 9f2b7ae8291..00000000000
--- a/src/test/run-pass/syntax-extension-fmt-istr.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-// FIXME: This test is transitional until estrs are gone.
-use std;
-fn main() {
-    let s = #fmt[~"%S", ~"test"];
-    assert s == "test";
-}
\ No newline at end of file